48TCA04---A12
Nominal 3 to 10 Tons
Wit h Puro n® (R---410A) Refrigerant
Service and Maintenance Instructions
TABLE OF CONTENTS
SAFETY CONSIDERATIONS1....................
UNIT ARRANGEMENT AND ACCESS2...........
SUPPLY FAN (BLOWER) SECTION4..............
COOLING5....................................
PURONR (R--410A) REFRIGERANT8..............
COOLING CHARGING CHARTS9.................
CONVENIENCE OUTLETS14....................
SMOKE DETECTORS15.........................
PROTECTIVE DEVICES22.......................
GAS HEATING SYSTEM22......................
PREMIERLINKT CONTROL34...................
RTU--MP CONTROL SYSTEM42..................
ECONOMI$ER SYSTEMS55......................
WIRING DIAGRAMS63.........................
PRE--START--UP66..............................
START--UP, GENERAL66........................
START--UP, PREMIERLINKT CONTROL68........
START--UP, RTU--MP CONTROL68................
OPERATING SEQUENCES71.....................
FASTENER TORQUE VALUES81.................
APPENDIX I. MODEL NUMBER SIGNIFICANCE82.
APPENDIX II. PHYSICAL DATA83................
APPENDIX III. FAN PERFORMANCE87...........
APPENDIX IV. ELECTRICAL DATA99.............
APPENDIX V. WIRING DIAGRAM LIST104........
APPENDIX VI. MOTORMASTER SENSOR
LOCATIONS105................................
UNIT START-UP CHECKLIST107.................
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment
can be hazardous due to system pressure and electrical
components. Only trained and qualified service personnel
shouldinstall,repair,orserviceair-conditioning
equipment. Untrained personnel can perform the basic
maintenance functions of replacing filters. Trained service
personnel should perform all other operations.
When working on air-conditioning equipment, observe
precautions in the literature, tags and labels attached to
the unit, and other safety precautions that may apply.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for unbrazing operations.
Havefireextinguishersavailableforallbrazing
operations.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for brazing operations. Have
fireextinguisher available.Read these instructions
thoroughly and follow all warnings or cautions attached to
the unit. Consult local building codes and National
Electrical Code (NEC) for special requirements.
Recognize safety information. This is the safety--alert
symbol
instructions or manuals, be alert to the potential for
personal injury.
Understand the signal words DANGER, WARNING, and
CAUTION. These words are used with the safety--alert
symbol. DANGER identifies the most serious hazards
which will result in severe personal injury or death.
WARNING signifies a hazard which could result in
personal injury or death. CAUTION is used to identify
unsafe practices which may result in minor personal
injury or product and property damage. NOTE is used to
highlight suggestions which will result in enhanced
installation, reliability, or operation.
. When you see this symbol on the unit and in
!
WARNING
!
WARNING
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in
personal injury, death and/or property damage.
Refer to the User’s Information Manual provided
with this unit for more details.
Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
What to do if you smell gas:
DO NOT try to light any appliance.
DO NOT touch any electrical switch, or use any
phone in your building.
IMMEDIATELY call your gas supplier from a
neighbor’sphone.Follow thegassupplier’s
48TC
instructions.
If you cannot reach your gas supplier, call the fire
department.
!
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
Before performing service or maintenance operations
on unit, turn off main power switch to unit. Electrical
shock and rotating equipment could cause injury.
!
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
Units with convenience outlet circuits may use
multiple disconnects. Check convenience outlet for
power status before opening unit for service. Locate
its disconnect switch, if appropriate, and open it.
Tag--out this switch, if necessary.
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury or death.
Disconnect gas piping from unit when pressure testing
at pressure greater than 0.5 psig. Pressures greater
than 0.5 psig will cause gas valve damage resulting in
hazardous condition. If gas valve is subjected to
pressure greater than 0.5 psig, it must be replaced
before use. When pressure testing field-supplied gas
piping at pressures of 0.5 psig or less, a unit connected
to such piping must be isolated by closing the manual
gas valve(s).
UNIT ARRANGEMENT AND ACCESS
General
Fig. 1 and Fig. 2 show general unit arrangement and
access locations.
FILTER ACCESS PANEL
COMPRESSOR
ACCESS PANEL (04-07 only)
OUTDOOR-AIR OPENING AND
INDOOR COIL ACCESS PANEL
C08449
Fig. 1 -- Typical Access Panel Locations
!
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage.
Puron (R--410A) refrigerant systems operate at higher
pressures than standard R--22 systems. Do not use
R--22 service equipment or components on Puron
refrigerant equipment.
BLOWER
ACCESS
PANEL
COMPRESSOR
(08-12 only)
Fig. 2 -- Blower Access Panel Location
CONTROL BOX
C08450
Routine Maintenance
These items should be part of a routine maintenance
program, to be checked every month or two, until a
specific schedule for each can be identified for this
installation:
2
Quarterly Inspection (and 30 days after initi al start)
R
S Return air filter replacement
S Outdoor hood inlet filters cleaned
S Belt tension checked
S Belt condition checked
S Pulley alignment checked
S Fan shaft bearing locking collar tightness checked
S Condenser coil cleanliness checked
S Condensate drain checked
Seasonal Maintenance
These items should be checked at the beginning of each
season (or more often if local conditions and usage
patterns dictate):
Conditioning
Air
S Condenser fan motor mounting bolts tightness
S Compressor mounting bolts
S Condenser fan blade positioning
S Control box cleanliness and wiring condition
S Wire terminal tightness
S Refrigerant charge level
S Evaporator coil cleaning
S Evaporator blower motor amperage
Heating
S Heat exchanger flue passageways cleanliness
S Gas burner condition
S Gas manifold pressure
S Heating temperature rise
Economizer or Outside Air
S Inlet filters condition
S Check damper travel (economizer)
S Check gear and dampers for debris and dirt
Air Filters and Scr
eens
Each unit is equipped with return air filters. If the unit has
an economizer, it will also have an outside air screen. If a
manual outside air damper is added, an inlet air screen
will also be present.
Each of these filters and screens will need to be
periodically replaced or cleaned.
Return Air
Filters
Return air filters are disposable fiberglass media type.
Access to the filters is through the small lift--out panel
located on the rear side of the unit, above the
evaporator/return air access panel. (See Fig. 1.)
Damper
To remove the filters:
1. Grasp the bottom flange of the upper panel.
2. Lift up and swing the bottom out until the panel disengages and pulls out.
3. Reach inside and extract the filters from the filter
rack.
4. Replace these filters as required with similar replacement filters of same size.
To re--install the access panel:
1. Slide the top of the panel up under the unit top panel.
2. Slide the bottom into the side channels.
3. Push the bottom flange down until it contacts the top
of the lower panel (or economizer top).
IMPORTANT:DONOTOPERATETHEUNIT
WITHOUT THESE FILTERS!
Outside Air
Hood
Outsideairhoodinletscreensarepermanent
aluminum--mesh type filters. Check these for cleanliness.
Remove the screens when cleaning is required. Clean by
washing with hot low--pressure water and soft detergent
and replace all screens before restarting the unit. Observe
the flow direction arrows on the side of each filter frame.
Economizer Inlet Air Screen
This air screen is retained by spring clips under the top
edge of the hood. (See Fig. 3.)
17 1/4”
DIVIDER
OUTSIDE
AIR
HOOD
CLEANABLE
BAROMETRIC
RELIEF
ALUMINUM
FILTER
FILTER
FILTE
CLIP
C06027
Fig. 3 -- Filter Installation
To remove the filter, open the spring clips. Re--install the
filter by placing the frame in its track, then closing the
spring clips.
48TC
Manual Outside Air Hood Screen
This inlet screen is secured by a retainer angle across the
top edge of the hood. (See Fig. 4.)
3
Fig. 4 -- Screens Installed on Outdoor--Air Hood
(Sizes 7--1/2 to 12--1/2 Tons Shown)
To remove the screen, loosen the screws in the top retainer
48TC
and slip the retainer up until the filter can be removed.
Re--install by placing the frame in its track, rotating the
retainer back down and tighten all screws.
SUPPLY F AN (BLOWER) SECTION
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could cause personal
injury or death.
Before performing service or maintenance operations
on the fan system, shut off all unit power and tag--out
the unit disconnect switch. Do not reach into the fan
section with power still applied to unit.
Supply Fan (Belt--Drive)
The supply fan system consists of a forward--curved
centrifugal blower wheel on a solid shaft with two
concentric type bearings, one on each side of the blower
housing. A fixed--pitch driven pulley is attached to the fan
shaft and an adjustable--pitch driver pulley is on the
motor. The pulleys are connected using a “V” type belt.
(See Fig. 5.)
C07156
inside surfaces. Check belt tension by using a spring--force
tool (such as Browning’s Part Number “Belt Tension
Checker” or equivalent tool); tension should be 6--lbs at a
5/8--in. deflection when measured at the centerline of the
belt span. This point is at the center of the belt when
measuring the distance between the motor shaft and the
blower shaft.
NOTE: Without the spring--tension tool, place a straight
edge across the belt surface at the pulleys, then deflect the
belt at mid--span using one finger to a 1/2--in. deflection.
Adjust belt tension by loosening the motor mounting plate
front bolts and rear bolt and sliding the plate toward the
fan (to reduce tension) or away from fan (to increase
tension). Ensure the blower shaft and the motor shaft are
parallel to each other (pulleys aligned). Tighten all bolts
when finished.
To replace the belt:
1. Use a belt with same section type or similar size. Do
not substitute a “FHP” type belt. When installing the
new belt, do not use a tool (screwdriver or pry--bar) to
force the belt over the pulley flanges, this will stress
the belt and cause a reduction in belt life.
2. Loosen the motor mounting plate front bolts and rear
bolts.
3. Push the motor and its mounting plate towards the
blower housing as close as possible to reduce the center distance between fan shaft and motor shaft.
4. Remove the belt by gently lifting the old belt over
one of the pulleys.
5. Install the new belt by gently sliding the belt over
both pulleys and then sliding the motor and plate
away from the fan housing until proper tension is
achieved.
6. Check the alignment of the pulleys, adjust if necessary.
7. Tighten all bolts.
8. Check the tension after a few hours of runtime and
re--adjust as required.
Adjustable--Pitch Pulley on
The motor pulley is an adjustable--pitch type that allows a
servicer to implement changes in the fan wheel speed to
match as--installed ductwork systems. The pulley consists
of a fixed flange side that faces the motor (secured to the
motor shaft) and a movable flange side that can be rotated
around the fixed flange side that increases or reduces the
pitch diameter of this driver pulley. (See Fig. 6.)
Motor
C07087
Fig. 5 -- Belt Drive Motor Mounting
Belt
Check the belt condition and tension quarterly. Inspect the
belt for signs of cracking, fraying or glazing along the
As the pitch diameter is changed by adjusting the position
of the movable flange, the centerline on this pulley shifts
laterally (along themotor shaft). This creates a
requirement for a realignment of the pulleys after any
adjustment of the movable flange. Also reset the belt
tension after each realignment.
Check the condition of the motor pulley for signs of wear.
Glazing of the belt contact surfaces and erosion on these
surfaces are signs of improper belt tension and/or belt
slippage. Pulley replacement may be necessary.
4
To change fan speed:
1. Shut off unit power supply.
2. Loosen belt by loosening fan motor mounting nuts.
(See Fig. 5.)
3. Loosen movable pulley flange setscrew. (See Fig. 6.)
4. Screw movable flange toward fixed flange to increase
speed and away from fixed flange to decrease speed.
Increasing fan speed increases load on motor. Do not
exceed maximum speed specified.
5. Set movable flange at nearest keyway of pulley hub
and tighten setscrew to torque specifications.
To align fan and motor pulleys:
1. Loosen fan pulley setscrews.
2. Slide fan pulley along fan shaft. Make angular alignment by loosening motor from mounting.
3. Tighten fan pulley setscrews and motor mounting
bolts to torque specifications.
4. Recheck belt tension.
Motor
When replacing the motor, also replace the external--tooth
lock washer (star washer) under the motor mounting base;
this is part of the motor grounding system. Ensure the
teeth on the lock washer are in contact with the motor’s
painted base. Tighten motor mounting bolts to 120 +/-- 12
in--lbs.
Changing fan wheel speed by changing pulleys: The
horsepower rating of the belt is primarily dictated by the
pitch diameter of the smaller pulley in the drive system
(typically the motor pulley in these units). Do not install a
replacement motor pulley with a smaller pitch diameter
than provided on the original factory pulley. Change fan
wheel speed by changing the fan pulley (larger pitch
diameter to reduce wheel speed, smaller pitch diameter to
increase wheel speed) or select a new system (both
pulleys and matching belt(s)).
Before changing pulleys to increase fan wheel speed,
check the fan performance at the target speed and airflow
rate to determine new motor loading (bhp). Use the fan
performance tables or use the Packaged Rooftop Builder
software program. Confirm that the motor in this unit is
capable of operating at the new operating condition. Fan
shaft loading increases dramatically as wheel speed is
increased.
48TC
C07075
Fig. 6 -- Supply--Fan Pulley Adjustment
Bearings
This fan system uses bearings featuring concentric split
locking collars. The collars are tightened through a cap
screw bridging the split portion of the collar. The cap
screw has a Torx T25 socket head. To tighten the locking
collar: Hold the locking collar tightly against the inner
race of the bearing and torque the cap screw to 65--70
in--lb (7.4--7.9 Nm). See Fig. 7.
To reduce vibration, replace the motor’s adjustable pitch
pulley with a fixed pitch pulley (after the final airflow
balance adjustment). This will reduce the amount of
vibration generated by the motor/belt--drive system.
COOLING
!
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage.
This system uses PuronR refrigerant which has
higher pressures than R--22 and other refrigerants. No
other refrigerant may be used in this system. Gauge
set, hoses, and recovery system must be designed to
handle Puron refrigerant. If unsure about equipment,
consult the equipment manufacturer.
Condenser Coil
The condenser coil is fabricated with round tube copper
hairpins and plate fins of various materials and/or coatings
(see Model Number Format in the Appendix to identify
the materials provided in this unit). The coil may be
one--row or composite--type two--row. Composite two--row
coils are two single--row coils fabricated with a single
return bend end tubesheet.
Fig. 7 -- Tightening Locking Collar
C08121
Condenser Coil Maintenance and Cleaning
Recommendation
Routine cleaning of coil surfaces is essential to maintain
proper operation of the unit. Elimination of contamination
and removal of harmful residues will greatly increase the
5
life of the coil and extend the life of the unit. The
following maintenance and cleaning procedures are
recommended as part of the routine maintenance activities
to extend the life of the coil.
Remove Surface Loaded
Fibers
Surface loaded fibers or dirt should be removed with a
vacuum cleaner. If a vacuum cleaner is not available, a
soft non--metallic bristle brush may be used. In either
case, the tool should be applied in the direction of the fins.
Coil surfaces can be easily damaged (fin edges can be
easily bent over and damage to the coating of a protected
coil) if the tool is applied across the fins.
NOTE: Use of a water stream, such as a garden hose,
against a surface loaded coil will drive the fibers and dirt
into the coil. This will make cleaning efforts more
difficult. Surface loaded fibers must be completely
removed prior to using low velocity clean water rinse.
48TC
Periodic Clean Water
Rinse
A periodic clean water rinse is very beneficial for coils
that are applied in coastal or industrial environments.
However, it is very important that the water rinse is made
with a very low velocity water stream to avoid damaging
the fin edges. Monthly cleaning as described below is
recommended.
Two--Row Coils
Clean coil as follows:
1. Turn off unit power, tag disconnect.
2. Remove top panel screws on condenser end of unit.
3. Remove condenser coil corner post. See Fig. 8. To
hold top panel open, place coil corner post between
top panel and center post. See Fig. 9.
C08205
Fig. 8 -- Cleaning Condenser Coil
Routine Cleaning of Coil
Surfaces
Periodic cleaning with TotalineR environmentally sound
coil cleaner is essential to extend the life of coils. This
cleanerisavailablefromCarrierReplacement
Components Division as part number P902--0301 for a one
gallon container, and part number P902--0305 for a 5
gallon container. It is recommended that all coils,
including standard aluminum, pre--coated, copper/copper
or E--coatedcoils becleanedwith theTotaline
environmentally sound coil cleaner as described below.
Coil cleaning should be part of the unit’s regularly
scheduled maintenance procedures to ensure long life of
the coil. Failure to clean the coils may result in reduced
durability in the environment.
Avoid use of:
S coil brighteners
S acid cleaning prior to painting
S high pressure washers
S poor quality water for cleaning
Totalineenvironmentallysoundcoilcleaneris
nonflammable, hypo allergenic, non bacterial, and a
USDA accepted biodegradable agent that will not harm
the coil or surrounding components such as electrical
wiring, painted metal surfaces, or insulation. Use of
non--recommended coil cleaners is strongly discouraged
since coil and unit durability could be affected.
C08206
Fig. 9 -- Propping Up Top Panel
4. Remove screws securing coil to compressor plate and
compressor access panel.
5. Remove fastener holding coil sections together at return end of condenser coil. Carefully separate the outer coil section 3 to 4 in. from the inner coil section.
See Fig. 10.
One--Row Coil
Wash coil with commercial coil cleaner. It is not
necessary to remove top panel.
C08207
Fig. 10 -- Separating Coil Sections
6
6. Use a water hose or other suitable equipment to flush
down between the 2 coil sections to remove dirt and
debris. Clean the outer surfaces with a stiff brush in
the normal manner.
7. Secure inner and outer coil rows together with a
field--supplied fastener.
8. Reposition the outer coil section and remove the coil
corner post from between the top panel and center
post. Reinstall the coil corner post and replace all
screws.
S 2--1/2 gallon garden sprayer
S Water rinse with low velocity spray nozzle
!
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in accelerated
corrosion of unit parts.
Harsh chemicals, household bleach or acid or basic
cleaners should not be used to clean outdoor or indoor
coils of any kind. These cleaners can be very difficult
to rinse out of the coil and can accelerate corrosion at
the fin/tube interface where dissimilar materials are in
contact. If there is dirt below the surface of the coil,
use the Totaline environmentally sound coil cleaner.
!
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in reduced
unit performance or unit shutdown.
High velocity water from a pressure washer, garden
hose, or compressed air should never be used to
clean a coil. The force of the water or air jet will
bend the fin edges and increase airside pressure drop.
1. Proper eye protection such as safety glasses is recommended during mixing and application.
2. Remove all surface loaded fibers and dirt with a vacuum cleaner as described above.
3. Thoroughly wet finned surfaces with clean water and
a low velocity garden hose, being careful not to bend
fins.
4. Mix Totaline environmentally sound coil cleaner in a
2--1/2 gallon garden sprayer according to the instructions included with the cleaner. The optimum solution
temperature is 100_F.
NOTE: Do NOT USE water in excess of 130_F, as th e
enzymatic activity will be destroyed.
5. Thoroughly apply Totaline environmentally sound
coil cleaner solution to all coil surfaces including
finned area, tube sheets and coil headers.
6. Hold garden sprayer nozzle close to finned areas and
apply cleaner with a vertical, up--and--down motion.
Avoid spraying in horizontal pattern to minimize potential for fin damage.
7. Ensure cleaner thoroughly penetrates deep into finned
areas.
8. Interior and exterior finned areas must be thoroughly
cleaned.
9. Finned surfaces should remain wet with cleaning
solution for 10 minutes.
10. Ensure surfaces are not allowed to dry before rinsing.
Reapplying cleaner as needed to ensure 10--minute
saturation is achieved.
11. Thoroughly rinse all surfaces with low velocity clean
water using downward rinsing motion of water spray
nozzle. Protect fins from damage from the spray
nozzle.
Evaporator Coil
Cleaning the Evaporator Coil
1. Turn unit power off. Install lockout tag. Remove
evaporator coil access panel.
2. If economizer or two--position damper is installed, remove economizer by disconnecting Molex plug and
removing mounting screws.
3. Slide filters out of unit.
4. Clean coil using a commercial coil cleaner or dishwasher detergent in a pressurized spray canister. Wash
both sides of coil and flush with clean water. For best
results, back--flush toward return--air section to remove foreign material. Flush condensate pan after
completion.
5. Reinstall economizer and filters.
6. Reconnect wiring.
7. Replace access panels.
Evaporator Coil M etering
The metering devices are multiple fixed--bore devices
(Acutrolt) swedged into the horizontal outlet tubes from
the liquid header, located at the entrance to each
evaporator coil circuit path. These are non--adjustable.
Service requires replacing the entire liquid header
assembly.
To check for possible blockage of one or more of these
metering devices, disconnect the supply fan contactor
(IFC) coil, then start the compressor and observe the
frosting pattern on the face of the evaporator coil. A frost
pattern should develop uniformly across the face of the
coil starting at each horizontal header tube. Failure to
develop frost at an outlet tube can indicate a plugged or a
missing orifice.
Devices
Refrigerant System Pressure Access Ports
There are two access ports in the system -- on the suction
tube near the compressor and on the discharge tube near
the compressor. These are brass fittings with black plastic
caps. The hose connection fittings are standard 1/4 SAE
male flare couplings.
The brass fittings are two--piece High Flow valves, with a
receptacle base brazed to the tubing and an integral
spring--closed check valve core screwed into the base.
48TC
7
(See Fig. 11.) This check valve is permanently assembled
into this core body and cannot be serviced separately;
replace the entire core body if necessary. Service tools are
available from RCD that allow the replacement of the
check valve core without having to recover the entire
system refrigerant charge. Apply compressor refrigerant
oil to the check valve core’s bottom o--ring. Install the
fitting body with 96 +/ --10 in--lbs of torque; do not
overtighten.
Refrigerant Charge
Amount of refrigerant charge is listed on the unit’s
nameplate.RefertoCarrierGTAC2--5Charging,
Recovery, Recycling and Reclamation training manual
and the following procedures.
Unit panels must be in place when unit is operating during
the charging procedure.
Charge
No
PURONR (R--410A) REFRIGERANT
This unit is designed for use with Puron (R--410A)
refrigerant. Do not use any other refrigerant in this
system.
Puron (R--410A) refrigerant is provided in pink (rose)
colored cylinders. These cylinders are available with and
48TC
without dip tubes; cylinders with dip tubes will have a
label indicating this feature. For a cylinder with a dip
tube, place the cylinder in the upright position (access
valve at the top) when removing liquid refrigerant for
charging. For a cylinder without a dip tube, invert the
cylinder (access valve on the bottom) when removing
liquid refrigerant.
Because Puron (R--410A) refrigerant is a blend, it is
strongly recommended that refrigerant always be removed
from the cylinder as a liquid. Admit liquid refrigerant into
the system in the discharge line. If adding refrigerant into
the suction line, use a commercial metering/expansion
device at the gauge manifold; remove liquid from the
cylinder, pass it through the metering device at the gauge
set and then pass it into the suction line as a vapor. Do not
remove Puron (R--410A) refrigerant from the cylinder as a
vapor.
Use standard evacuating techniques. After evacuating
system, weigh in the specified amount of refrigerant.
Low--Charge
Cooling
Using Cooling Charging Charts, Fig. 12, vary refrigerant
until the conditions of the appropriate chart are met. Note
the charging charts are different from type normally used.
Charts are based on charging the units to the correct
superheat for the various operating conditions. Accurate
pressure gauge and temperature sensing device are
required. Connect the pressure gauge to the service port
on the suction line. Mount the temperature sensing device
on the suction line and insulate it so that outdoor ambient
temperature does not affect the reading. Indoor--air cfm
must be within the normal operating range of the unit.
To Use Cooling Charging
Charts
Take the outdoor ambient temperature and read the
suction pressure gauge. Refer to chart to determine what
suction temperature should be. If suction temperature is
high, add refrigerant. If suction temperature is low,
carefully recover some of the charge. Recheck the suction
pressure as charge is adjusted.
5/8” HEX
SEAT
.47
1/2-20 UNF RH
0.596
o
30
WASHER
O-RING
This surface provides a metal to metal seal when
torqued into the seat. Appropriate handling is
required to not scratch or dent the surface.
Fig. 11 -- CoreMax Access Port Assembly
8
CORE
(Part No. EC39EZ067)
1/2" HEX
o
45
DEPRESSOR PER ARI 720
+.01/-.035
FROM FACE OF BODY
Power failure.Call power company.
Fuse blown or circuit breaker tripped.Replace fuse or reset circuit breaker.
Compressor and Condenser
Fan Will Not Start.
Compressor Will Not Start But
Condenser Fan Runs.
Compressor Cycles (other
than normally satisfying thermostat).
Compressor Operates
Continuously.
Excessive Head Pressure.
Head Pressure Too Low.
Excessive Suction Pressure.
Suction Pressure Too Low.
Evaporator Fan Will Not Shut
Off.
Compressor Makes Excessive
Noise.
Defective thermostat, contactor, transformer,
or control relay.
Insufficient line voltage.Determine cause and correct.
Incorrect or faulty wiring.Check wiring diagram and rewire correctly.
Thermostat setting too high.Lower thermostat setting below room temperature.
Faulty wiring or loose connections in
compressor circuit.
Compressor motor burned out, seized, or
internal overload open.
Defective compressor.Replace and determine cause.
Insufficient line voltage.Determine cause and correct.
Blocked condenser.Determine cause and correct.
Defective run/start capacitor, overload, or start
relay.
Defective thermostat.Replace thermostat.
Faulty condenser--- fan motor or capacitor.Replace.
Restriction in refrigerant system.Locate restriction and remove.
Dirty air filter.Replace filter.
Unit undersized for load.Decrease load or increase unit size.
Thermostat set too low.Reset thermostat.
Low refrigerant charge.Locate leak; repair and recharge.
Leaking valves in compressor.Replace compressor.
Air in system.Recover refrigerant, evacuate system, and recharge.
Condenser coil dirty or restricted.Clean coil or remove restriction.
Dirty air filter.Replace filter.
Dirty condenser coil.Clean coil.
Refrigerant overcharged.Recover excess refrigerant.
Air in system.Recover refrigerant, evacuate system, and recharge.
Condenser air restricted or air short --- cycling.Determine cause and correct.
Low refrigerant charge.Check for leaks; repair and recharge.
Compressor valves leaking.Replace compressor.
Restrictioninliquidtube.Remove restriction.
High head load.Check for source and eliminate.
Compressor valves leaking.Replace compressor.
Refrigerant overcharged.Recover excess refrigerant.
Dirty air filter.Replace filter.
Low refrigerant charge.Check for leaks; repair and recharge.
Metering device or low side restricted.Remove source of restriction.
Insufficient evaporator airflow.
Temperature too low in conditioned area.Reset thermostat.
Outdoor ambient below 25˚F.Install low---ambient kit.
Time off delay not finished.W a i t f o r 3 0 --- s e con d o f f delay.
Compressor rotating in wrong direction.Reversethe3---phasepowerleads.
Replace component.
Check wiring and repair or replace.
Determine cause. Replace compressor.
Determine cause and replace.
Replace fuse or reset circuit breaker. Determine
cause.
Recover refrigerant, evacuate system, and recharge
to nameplate.
Determine cause and replace.
Increase air quantity. Check filter and replace if
necessary.
48TC
13
Compressor
Lubrication
The compressor is charged with the correct amount of oil
at the factory.
!
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in damage to
components.
The compressor is in a PuronR refrigerant system and
uses a polyolester (POE) oil. This oil is extremely
hygroscopic, meaning it absorbs water readily. POE
oils can absorb 15 times as much water as other oils
designed for HCFC and CFC refrigerants. Avoid
exposure of the oil to the atmosphere.
48TC
Replacing Compressor
2. Remove condenser--fan assembly (grille, motor, and
fan).
3. Loosen fan hub setscrews.
4. Adjust fan height as shown in Fig. 13.
5. Tighten setscrews.
6. Replace condenser--fan assembly.
Conduit
0.14 in + 0.0 / -0.03
C08448
Fig. 13 -- Condenser Fan Adjustment
Troubleshooting Cooling System
Refer to Table 1 for additional troubleshooting topics.
The compressor used with Puron refrigerant contains a
POE oil. This oil has a high affinity for moisture. Do not
remove the compressor’s tube plugs until ready to insert
the unit suction and discharge tube ends.
Compressor mounting bolt torque is 65--75 ft--lbs.
Compressor
On 3--phase units with scroll compressors, it is important
to be certain compressor is rotating in the proper
direction. To determine whether or not compressor is
rotating in the proper direction:
1. Connect service gauges to suction and discharge pressure fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge
pressure should rise, as is normal on any start--up.
NOTE:If the suction pressure does not drop and the
discharge pressure does not rise to normal levels:
4. Note that the evaporator fan is probably also rotating
in the wrong direction.
5. Turn off power to the unit.
6. Reverse any two of the unit power leads.
7. Reapply power to the compressor.
The suction and discharge pressure levels should now
move to their normal start--up levels.
NOTE: When the compressor is rotating in the wrong
direction, the unit makes an elevated level of noise and
does not provide cooling.
Rotation
Filter Drier
CONVENIENCE OUTLETS
!
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
Units with convenience outlet circuits may use
multiple disconnects. Check convenience outlet for
power status before opening unit for service. Locate
its disconnect switch, if appropriate, and open it.
Tag--out this switch, if necessary.
Two types of convenience outlets are offered on 48TC
models: Non--powered and unit--powered. Both types
providea125--voltGFCI(ground--fault
circuit--interrupter) duplex receptacle rated at 15--A
behind a hinged waterproof access cover, located on the
end panel of the unit. See Fig. 14.
Pwd-CO Transformer
Conv Outlet
GFCI
Pwd-CO
Fuse
Switch
Replace whenever refrigerant system is exposed to
atmosphere. Only use factory specified liquid--line filter
driers with working pressures no less than 650 psig. Do
not install a suction--line filter drier in liquid line. A
liquid--line filter drier designed for use with Puron
refrigerant is required on every unit.
Condenser--Fan Adjustment
1. Shut off unit power supply. Install lockout tag.
C08128
Fig. 14 -- Convenience Outlet Location
Non--powered type:Thistype requires thefield
installation of a general--purpose 125--volt 15--A circuit
powered from a source elsewhere in the building. Observe
national and local codes when selecting wire size, fuse or
14
breaker requirements and disconnect switch size and
location. Route 125--v power supply conductors into the
bottom of the utility box containing the duplex receptacle.
Unit--powered type: A unit--mounted transformer is
factory--installed to stepdown the main power supply
voltage to the unit to 115--v at the duplex receptacle. This
option also includes a manual switch with fuse, located in
a utility box and mounted on a bracket behind the
convenience outlet; access is through the unit’s control
box access panel. See Fig. 14.
The primary leads to the convenience outlet transformer
are not factory--connected. Selection of primary power
source is a customer--option. If local codes permit, the
transformer primary leads can be connected at the
line--sideterminalsonaunit--mountednon--fused
disconnect or HACR breaker switch; this will provide
service power to the unit when the unit disconnect switch
or HACR switch is open. Other connection methods will
result in the convenience outlet circuit being de--energized
when the unit disconnect or HACR switch is open. See
Fig. 15.
lamps, etc; it is not intended to provide 15--amps loading
for continuous duty loads (such as electric heaters for
overnight use). Observe a 50% limit on circuit loading
above 8--amps (i.e., limit loads exceeding 8--amps to 30
minutes of operation every hour).
Maintenance: Periodically test the GFCI receptacle by
pressing the TEST button on the face of the receptacle.
This should cause the internal circuit of the receptacle to
trip and open the receptacle. Check for proper grounding
wires and power line phasing if the GFCI receptacle does
not trip as required. Press the RESET button to clear the
tripped condition.
Fuse on powered type: The factory fuse is a Bussman
“Fusetron” T--15, non--renewable screw--in (Edison base)
type plug fuse.
Using unit--mounted convenience outlets: Units with
unit--mounted convenience outlet circuits will often
require that two disconnects be opened to de--energize all
power to the unit. Treat all units as electrically energized
until the convenience outlet power is also checked and
de--energization is confirmed. Observe National Electrical
Code Article 210, Branch Circuits, for use of convenience
outlets.
48TC
CO8283
Fig. 15 -- Powered Convenience Outlet Wiring
UNIT
VOLTAGE
208,
230
460480
575600
CONNECT
AS
240
PRIMARY
CONNECTIONS
L1: RED +YEL
L2: BLU + GRA
L1: RED
Splice BLU + YEL
L2: GRA
L1: RED
L2: GRA
TRANSFORMER
TERMINALS
H1 + H3
H2 + H4
H1
H2 + H3
H4
H1
H2
Duty Cycle: The unit--powered convenience outlet has a
duty cycle limitation. The transformer is intended to
provide power on an intermittent basis for service tools,
SMOKE DETECTORS
Smoke detectors are available as factory--installed options
on 48TC models. Smoke detectors may be specified for
Supply Air only or for Return Air without or with
economizer or in combination of Supply Air and Return
Air. Return Air smoke detectors are arranged for vertical
return configurations only. All components necessary for
operation are factory--provided and mounted. The unit is
factory--configuredforimmediatesmokedetector
shutdown operation; additional wiring or modifications to
unit terminal board may be necessary to complete the unit
and smoke detector configuration to meet project
requirements.
System
The smoke detector system consists of a four--wire
controller and one or two sensors. Its primary function is
to shut down the rooftop unit in order to prevent smoke
from circulating throughout the building. It is not to be
used as a life saving device.
Controller
The controller (see Fig. 16) includes a controller housing,
a printed circuit board, and a clear plastic cover. The
controller can be connected to one or two compatible duct
smoke sensors. The clear plastic cover is secured to the
housing with a single captive screw for easy access to the
wiring terminals. The controller has three LEDs (for
Power, Trouble and Alarm) and a manual test/reset button
(on the cover face).
15
Duct smoke sensor
controller
Conduit nuts
(supplied by installer)
Conduit sup port plate
Controller housing
and electronics
Conduit cou plings
(supplied by installer)
Fastener
(2X)
Terminal block cover
Cover gasket
(ordering option)
48TC
Alarm
Troub le
Power
Tes t / r e s e t
switch
Fig. 16 -- Controller Assembly
Sensor
The sensor (see Fig. 17) includes a plastic housing, a
printed circuit board, a clear plastic cover, a sampling
tube inlet and an exhaust tube. The sampling tube (when
used) and exhaust tube are attached during installation.
The sampling tube varies in length depending on the size
of the rooftop unit. The clear plastic cover permits visual
inspections without having to disassemble the sensor. The
cover attaches to the sensor housing using four captive
screws and forms an airtight chamber around the sensing
electronics. Each sensor includes a harness with an RJ45
terminal for connecting to the controller. Each sensor has
four LEDs (for Power, Trouble, Alarm and Dirty) and a
manual test/reset button (on the left--side of the housing).
Air is introduced to the duct smoke detector sensor’s
sensing chamber through a sampling tube that extends into
the HVAC duct and is directed back into the ventilation
system through a (shorter) exhaust tube. The difference in
air pressure between the two tubes pulls the sampled air
through the sensing chamber. When a sufficient amount of
smoke is detected in the sensing chamber, the sensor
signals an alarm state and the controller automatically
takes the appropriate action to shut down fans and
blowers, change over air handling systems, notify the fire
alarm control panel, etc.
The sensor uses a process called differential sensing to
prevent gradual environmental changes from triggering
false alarms. A rapid change in environmental conditions,
such as smoke from a fire, causes the sensor to signal an
alarm state but dust and debris accumulated over time
does not.
Controll er cover
C08208
Duct smoke s ensor
Exhaust tube
See
Detail A
Detail A
Intake
gasket
Plug
TSD-CO2
(ordering option)
Sampling tube
(ordered separately)
Magnetic
test/reset
switch
Exhaust gasket
Coupling
Alarm
Troub le
Sensor housing
and electro nics
Power
Dirty
Cover gasket
(ordering option)
Sensor cover
C08209
Fig. 17 -- Smoke Detector Sensor
For installations using two sensors, the duct smoke
detector does not differentiate which sensor signals an
alarm or trouble condition.
Smoke Detector Locations
Supply Air — The Supply Air smoke detector sensor is
located to the left of the unit’s indoor (supply) fan. See
Fig. 18. Access is through the fan access panel. There is
no sampling tube used at this location. The sampling tube
inlet extends through the side plate of the fan housing
(into a high pressure area). The controller is located on a
bracket to the right of the return filter, accessed through
the lift--off filter panel.
Smoke Detector Sensor
C08245
Fig. 18 -- Typical Supply Air Smoke Detector Sensor
Location
16
Return Air without Economizer — The sampling tube is
located across the return air opening on the unit basepan.
See Fig. 19. The holes in the sampling tube face
downward, into the return air stream. The sampling tube is
connected via tubing to the return air sensor that is
mounted on a bracket high on the partition between return
filter and controller location. (This sensor is shipped in a
flat--mounting location. Installation requires that this
sensor be relocated to its operating location and the tubing
to the sampling tube be connected. See installation steps
below.)
Return Air Detector module
(shipping position shown)*
Controller module
Completing Installation of Return Air Smoke
Sensor:
Screws
Flexible
Exhaust Tubes
Sample Tube
C08126
Fig. 21 -- Return Air Detector Shipping Position
Return Air Detector Sampling Tube
*RA detector must be moved from shipping position to operating position by installer
C07307
Fig. 19 -- Typical Return Air Detector Location
Return Air with Economizer — The sampling tube is
inserted through the side plates of the economizer
housing, placing it across the return air opening on the
unit basepan. See Fig. 20. The holes in the sampling tube
face downward, into the return air stream. The sampling
tube is connected via tubing to the return air sensor that is
mounted on a bracket high on the partition between return
filter and controller location. (This sensor is shipped in a
flat--mounting location. Installation requires that this
sensor be relocated to its operating location and the tubing
to the sampling tube be connected. See installation steps
below.)
1. Unscrew the two screws holding the Return Air
Sensor detector plate. See Fig. 21. Save the screws.
2. Remove the Return Air Sensor and its detector plate.
3. Rotate the detector plate so the sensor is facing outwards and the sampling tube connection is on the bottom. See Fig. 22.
4. Screw the sensor and detector plate into its operating
position using screws from Step 1. Make sure the
sampling tube connection is on the bottom and the exhaust tube is on the top. See Fig. 22.
5. Connect the flexible tube on the sampling inlet to the
sampling tube on the basepan.
6. For units with an economizer, the sampling tube is integrated into the economizer housing but the connection of the flexible tubing to the sampling tube is the
same.
48TC
Return Air
Sampling Tube
Fig. 20 -- Return Air Sampling Tube Location
C08129
C08127
Fig. 22 -- Return Air Sensor Operating Position
FIOP Smoke Detector Wiring and Response
All units: FIOP smokedetector is configured to
automatically shut down all unit operations when smoke
condition is detected. See Fig. 23, Smoke Detector
Wiring.
Highlight A: JMP 3 is factory--cut, transferring unit
control to smoke detector.
Highlight B: Smoke detector NC contact set will open on
smokealarmcondition,de--energizingtheORN
conductor.
17
B
D
C
F
E
48TC
Fig. 23 -- Typical Smoke Detector System Wiring
Highlight C: 24--v power signal via ORN lead is removed
at Smoke Detector input on LCTB; all unit operations
cease immediately.
PremierLink and RTU--MP Controls: Unit operating
functions (fan, cooling and heating) are terminated as
described above. In addition:
Highlight D: On smoke alarm condition, the smoke
detector NO Alarm contact will close, supplying 24--v
power to GRA conductor.
Highlight E: GRA lead at Smoke Alarm input on LCTB
provides 24--v signal to FIOP DDC control.
Premier--Link: This signal is conveyed to PremierLink
FIOP’s TB1 at terminal TB1--6 (BLU lead). This signal
initiates the FSD sequence by the PremierLink control.
FSD status is reported to connected CCN network.
RTU--MP: The 24--v signal is conveyed to RTU--MP’s
J1--10 input terminal. This signal initiates the FSD
sequence by the RTU--MP control. FSD status is reported
to connected BAS network.
Using Remote Logic: Five conductors are provided for
field use (see Highlight F) for additional annunciation
functions.
Additional Application Data — Refer to Catalog No.
HKRNKA--1XA for discussions on additional control
features of these smoke detectors including multiple unit
coordination. See Fig. 23.
A
C08246
Sensor and Controller Tests
Sensor Alarm Test
The sensor alarm test checks a sensor’s ability to signal an
alarm state. This test requires that you use a field provided
SD--MAG test magnet.
!
CAUTION
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
This test places the duct detector into the alarm state.
Unless part of the test, disconnect all auxiliary
equipment from the controller before performing the
test. If the duct detector is connected to a fire alarm
system,notifytheproperauthoritiesbefore
performing the test.
Sensor Alarm Test Procedure
1. Hold the test magnet where indicated on the side of
the sensor housing for seven seconds.
2. Verify that the sensor’s Alarm LED turns on.
3. Reset the sensor by holding the test magnet against
the sensor housing for two seconds.
4. Verify that the sensor’s Alarm LED turns off.
Controller Alarm T
The controller alarm test checks the controller’s ability to
initiate and indicate an alarm state.
est
18
!
CAUTION
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
This test places the duct detector into the alarm state.
Disconnect all auxiliary equipment from the controller
before performing the test. If the duct detector is
connected to a fire alarm system, notify the proper
authorities before performing the test.
Controller Alarm Test Procedure
1. Press the controller’s test/reset switch for seven
seconds.
2. Verify that the controller’s Alarm LED turns on.
3. Reset the sensor by pressing the test/reset switch for
two seconds.
4. Verify that the controller’s Alarm LED turns off.
Dirty Controller T
The dirty controller test checks the controller’s ability to
initiate a dirty sensor test and indicate its results.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
Pressing the controller’s test/reset switch for longer
than seven seconds will put the duct detector into the
alarm state and activate all automatic alarm responses.
Dirty Controller Test Procedure
1. Press the controller’s test/reset switch for two
seconds.
2. Verify that the controller’s Trouble LED flashes.
Dirty Sensor T
The dirty sensor test provides an indication of the sensor’s
ability to compensate for gradual environmental changes.
A sensor that can no longer compensate for environmental
changes is considered 100% dirty and requires cleaning or
replacing. You must use a field provided SD--MAG test
magnet to initiate a sensor dirty test. The sensor’s Dirty
LED indicates the results of the dirty test as shown in
Table 2.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
Holding the test magnet against the sensor housing for
more than seven seconds will put the duct detector
into the alarm state and activate all automatic alarm
responses.
est
!
CAUTION
est
!
CAUTION
Tabl e 2 – D i rty LED Te s t
FLASHESDESCRIPTION
10---25% dirty. (Typical of a newly installed detector)
225---50% dirty
351---75% dirty
476---99% dirty
Dirty Sensor Test Procedure
1. Hold the test magnet where indicated on the side of
the sensor housing for two seconds.
2. Verify that the sensor’s Dirty LED flashes.
!
CAUTION
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
Changing the dirty sensor test operation will put the
detector into the alarm state and activate all automatic
alarm responses. Before changing dirty sensor test
operation, disconnect all auxiliary equipment from the
controller and notify the proper authorities if
connected to a fire alarm system.
Changing the Dirt Sensor Test
By default, sensor dirty test results are indicated by:
S The sensor’s Dirty LED flashing.
S The controller’s Trouble LED flashing.
S The controller’s supervision relay contacts toggle.
The operation of a sensor’s dirty test can be changed so
that the controller’s supervision relay is not used to
indicate test results. When two detectors are connected to
a controller, sensor dirty test operation on both sensors
must be configured to operate in the same manner.
To Configure the Dirty Sensor Test Operation
1. Hold the test magnet where indicated on the side of
the sensor housing until the sensor’s Alarm LED turns
on and its Dirty LED flashes twice (approximately 60
seconds).
2. Reset the sensor by removing the test magnet then
holding it against the sensor housing again until the
sensor’s Alarm LED turns off (approximately 2
seconds).
Remote Station T
The remote station alarm test checks a test/reset station’s
ability to initiate and indicate an alarm state.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
This test places the duct detector into the alarm state.
Unless part of the test, disconnect all auxiliary
equipment from the controller before performing the
test. If the duct detector is connected to a fire alarm
system,notifytheproperauthoritiesbefore
performing the test.
est
!
CAUTION
48TC
19
SD--TRK4 Remote Alarm Test Procedure
1. Turn the key switch to the RESET/TEST position for
seven seconds.
2. Verify that the test/reset station’s Alarm LED turns
on.
3. Reset the sensor by turning the key switch to the
RESET/TEST position for two seconds.
4. Verify that the test/reset station’s Alarm LED turns
off.
Remote Test/Reset Station Dirty Sensor T
est
The test/reset station dirty sensor test checks the test/reset
station’s ability to initiate a sensor dirty test and indicate
the results. It must be wired to the controller as shown in
Fig. 24 and configured to operate the controller’s
supervision relay. For more information, see “Changing
sensor dirty test operation.”
48TC
12
1
TB3
1
2
Smoke Detector Controller
−
Auxiliary
equipment
+
Dirty Sensor Test Using an SD--TRK4
1. Turn the key switch to the RESET/TEST position for
two seconds.
2. Verify that the test/reset station’s Trouble LED
flashes.
Detector Cleaning
Cleaning the Smoke Detector
Clean the duct smoke sensor when the Dirty LED is
flashing continuously or sooner if conditions warrant.
!
CAUTION
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
If the smoke detector is connected to a fire alarm
system, first notify the proper authorities that the
detector is undergoing maintenance then disable the
relevant circuit to avoid generating a false alarm.
1. Disconnect power from the duct detector then remove
the sensor’s cover. (See Fig. 25.)
3
S
contacts [3]
Wire m
ust be
added by installer
upe
rv
ision relay
14
SD-TRK4
1
3
18 Vdc ( )
18 Vdc ( )
+
−
19
15
2
20
Trouble
5
P
ower
4
Alarm
1
Reset/Test
3
2
C08247
Fig. 24 -- Remote Test/Reset Station Connections
!
CAUTION
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
If the test/reset station’s key switch is left in the
RESET/TEST position for longer than seven seconds,
the detector will automatically go into the alarm state
and activate all automatic alarm responses.
!
CAUTION
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in personnel
and authority concern.
Holding the test magnet to the target area for longer
than seven seconds will put the detector into the alarm
state and activate all automatic alarm responses.
Sampling
tube
Airow
HVAC duct
Sensor
housing
Optic
plate
Retainer
clip
Optic
housing
C07305
Fig. 25 -- Sensor Cleaning Diagram
2. Using a vacuum cleaner, clean compressed air, or a
soft bristle brush, remove loose dirt and debris from
inside the sensor housing and cover.
Use isopropyl alcohol and a lint--free cloth to remove
dirt and other contaminants from the gasket on the
sensor’s cover.
3. Squeeze the retainer clips on both sides of the optic
housing then lift the housing away from the printed
circuit board.
4. Gently remove dirt and debris from around the optic
plate and inside the optic housing.
5. Replace the optic housing and sensor cover.
6. Connect power to the duct detector then perform a
sensor alarm test.
INDICAT ORS
Normal State
The smoke detector operates in the normal state in the
absence of any trouble conditions and when its sensing
chamber is free of smoke. In the normal state, the Power
20
LED on both the sensor and the controller are on and all
other LEDs are off.
Alarm
State
The smoke detector enters the alarm state when the
amount of smoke particulate in the sensor’s sensing
chamber exceeds the alarm threshold value. (See Table 3.)
Upon entering the alarm state:
S The sensor’s Alarm LED and the controller’s Alarm LED
turn on.
S The contacts on the controller’s two auxiliary relays
switch positions.
S The contacts on the controller’s alarm initiation relay
close.
S The controller’s remote alarm LED output is activated
(turned on).
S The controller’s high impedance multiple fan shutdown
control line is pulled to ground Trouble state.
The SuperDuct duct smoke detector enters the trouble
state under the following conditions:
S A sensor’s cover is removed and 20 minutes pass before
it is properly secured.
S A sensor’s environmental compensation limit is reached
(100% dirty).
S A wiring fault between a sensor and the controller is
detected.
An internal sensor fault is detected upon entering the
trouble state:
S The contacts on the controller’s supervisory relay switch
positions. (See Fig. 26.)
S If a sensor trouble, the sensor’s Trouble LED the
controller’s Trouble LED turn on.
S If 100% dirty, the sensor’s Dirty LED turns on and the
controller’s Trouble LED flashes continuously.
S If a wiring fault between a sensor and the controller, the
controller’s Trouble LED turns on but not the sensor’s.
Tro uble
Alarm
Power
Test/reset
switch
NOTE:All troubles are latched by the duct smoke
detector. The trouble condition must be cleared and then
the duct smoke detector must be reset in order to restore it
to the normal state.
Resetting Alarm and Tr ouble Condition T
rips:
Manual reset is required to restore smoke detector systems
to Normal operation. For installations using two sensors,
the duct smoke detector does not differentiate which
sensor signals an alarm or trouble condition. Check each
sensor for Alarm or Trouble status (indicated by LED).
Clear the condition that has generated the trip at this
sensor. Then reset the sensor by pressing and holding the
reset button (on the side) for 2 seconds. Verify that the
sensor’s Alarm and Trouble LEDs are now off. At the
controller, clear its Alarm or Trouble state by pressing and
holding the manual reset button (on the front cover) for 2
seconds. Verify that the controller’s Alarm and Trouble
LEDs are now off. Replace all panels.
Troubleshooting
Controller’s Trouble LED is On
1. Check the Trouble LED on each sensor connected to
the controller. If a sensor’s Trouble LED is on, determine the cause and make the necessary repairs.
2. Check the wiring between the sensor and the controller. If wiring is loose or missing, repair or replace as
required.
Controller’s Trouble LED is
1. One or both of the sensors is 100% dirty.
2. Determine which Dirty LED is flashing then clean
that sensor assembly as described in the detector
cleaning section.
Sensor’s Trouble LED is
1. Check the sensor’s Dirty LED. If it is flashing, the
sensor is dirty and must be cleaned.
2. Check the sensor’s cover. If it is loose or missing, secure the cover to the sensor housing.
3. Replace sensor assembly.
Sensor’s Power LED is
1. Check the controller’s Power LED. If it is off, determine why the controller does not have power and
make the necessary repairs.
2. Check the wiring between the sensor and the controller. If wiring is loose or missing, repair or replace as
required.
Flashing
On
Off
48TC
C07298
Fig. 26 -- Controller Assembly
Table 3 – Detector Indicators
CONTROL OR INDICATORDESCRIPTION
Magnetic test/reset switch
Alarm LEDIndicates the sensor is in the alarm state.
Troubl e LEDIndicates the sensor is in the trouble state.
Dirty LED
Power LEDIndicates the sensor is energized.
Resets the sensor when it is in the alarm or trouble state. Activates or tests the sensor when it is in
the normal state.
Indicates the amount of environmental compensation used by the sensor
(flashing continuously = 100%)
21
Controller’s Power LED is Off
1. Make sure the circuit supplying power to the controller is operational. If not, make sure JP2 and JP3 are
set correctly on the controller before applying power.
2. Verify that power is applied to the controller’s supply
input terminals. If power is not present, replace or repair wiring as required.
Remote Test/Reset Station’s Trouble LED Does
flash When Performing a Dirty Test, But the Contr
ler’s Trouble LED
Does
1. Verify that the remote test/station is wired as shown
in Fig. 24. Repair or replace loose or missing wiring.
2. Configure the sensor dirty test to activate the controller’s supervision relay. See “Changing sensor dirty
test operation.”
Sensor’s Trouble LED is On, But the Controller’
Tr ouble LED is
48TC
OFF
Remove JP1 on the controller.
Not
s
ol-
The standard supply fan motor is equipped with internal
overcurrent and overtemperature protection. Protection
devices reset automatically.
The High Static option supply fan motor is equipped with
a pilot--circuit Thermix combination overtemperature/
overcurrentprotectiondevice.Thisdeviceresets
automatically. Do not bypass this switch to correct
trouble. Determine the cause and correct it.
Condenser Fan Motor Pr
otection
The condenser fan motor is internally protected against
overtemperature.
Relief Device
A soft solder joint at the suction service access port
provides pressure relief under abnormal temperature and
pressure conditions (i.e., fire in building). Protect this
joint during brazing operations near this joint.
Control Circuit, 24--V
PROTECTIVE DEVICES
Compressor Protection
Overcurrent
The compressor has internal linebreak motor protection.
Overtemperatur
The compressor has an internal protector to protect it
against excessively high discharge gas temperatures.
High Pressure
The system is provided with a high pressure switch
mountedonthedischargeline.Theswitchis
stem--mounted and brazed into the discharge tube. Trip
setting is 630 psig +/-- 10 psig (4344 +/-- 69 kPa) when
hot. Reset is automatic at 505 psig (3482 kPa).
Low Pressure
The system is protected against a loss of charge and low
evaporator coil loading condition by a low pressure switch
located on the suction line near the compressor. The
switch is stem--mounted. Trip setting is 54 psig +/-- 5 psig
(372 +/-- 34 kPa). Reset is automatic at 117 +/-- 5 psig
(807 +/-- 34 kPa).
Evaporator Freeze Pr
e
Switch
Switch
otection
The control circuit is protected against overcurrent
conditions by a circuit breaker mounted on control
transformer TRAN. Reset is manual.
GAS HEATING SYSTEM
General
The heat exchanger system consists of a gas valve feeding
multiple inshot burners off a manifold. The burners fire
into matching primary tubes. The primary tubes discharge
into combustion plenum where gas flow converges into
secondary tubes. The secondary tubes exit into the
induced draft fan wheel inlet. The induced fan wheel
discharges into a flue passage and flue gases exit out a
flue hood on the side of the unit. The induced draft fan
motor includes a Hall Effect sensor circuit that confirms
adequate wheel speed via the Integrated Gas Control
(IGC) board. Safety switches include a Rollout Switch (at
the top of the burner compartment) and a limit switch
(mounted through the fan deck, over the tubes). (See Fig.
27 and Fig. 28.)
INDUCEDDRAFT
MOTOR
MOUNTING
PLATE
ROLLOUT
SWITCH
The system is protected against evaporator coil frosting
and low temperature conditions by a temperature switch
mounted on the evaporator coil hairpin. Trip setting is
30_F+/--5_F(--1_C+/--3_C). Reset is automatic at 45_F
(7_C).
Supply (Indoor) Fan Motor Pr
otection
Disconnect and lockout power when servicing fan motor.
22
BURNER
SECTION
INDUCEDDRAFT
MOTOR
MANIFOLD
PRESSURE
TAP
Fig. 27 -- Burner Section Details
FLUE
EXHAUST
VESTIBULE
PLATE
BLOWER
HOUSING
GAS
VALV E
C06152
Limit Switch
and Shield
C08284
Fig. 28 -- Limit Switch Location
Fuel Types and Pressures
Natural Gas — The 48TC unit is factory--equipped for use
with Natural Gas fuel at elevation under 2000 ft (610 m).
See section Orifice Replacement for information in
modifying this unit for installation at elevations above
2000 ft (610 m).
Gas line pressure entering the unit’s main gas valve must
be within specified ranges. Adjust unit gas regulator valve
as required or consult local gas utility.
Table 4 – Natural Gas Supply Line Pressure Ranges
UNIT MODELUNIT SIZEMINMAX
48TCAll
4.0 in. wg
(996 Pa)
13.0 in. wg
(3240 Pa)
Table 6 – Liquid Propane Supply Line Pressure Ranges
UNIT MODELUNIT SIZEMINMAX
48TCD,E,F
48TCS,R,T
48TCL,M,NAllNANA
All
11.0 in. wg
(2740 Pa)
13.0 in. wg
(3240 Pa)
Manifold pressure for LP fuel use must be adjusted to
specified range. Follow instructions in the accessory kit to
make initial readjustment.
Table 7 – Liquid Propane Manifold Pressure Ranges
UNIT MODELUNIT SIZEHIGH FIRELOW FIRE
48TCD,S
48TCE,R
48TCF,T
48TCL,
48TCM,
48TCN
NA: Not Available
{ 3 Phase models only
All
AllNANA
10.0 in. wg
(2490 Pa)
5.0 in. wg
(1245 Pa){
Supply Pressure Switch — The LP conversion kit includes
a supply low pressure switch. The switch contacts (from
terminal C to terminal NO) will open the gas valve power
whenever the supply line pressure drops below the
setpoint. See Fig. 29 and Fig. 30. If the low pressure
remains open for 15 minutes during a call for heat, the
IGC circuit will initiate a Ignition Fault (5 flashes)
lockout. Reset of the low pressure switch is automatic on
rise in supply line pressure. Reset of the IGC requires a
recycle of unit power after the low pressure switch has
closed.
48TC
Manifold pressure is factory--adjusted for NG fuel use.
Adjust as required to obtain best flame characteristic.
Table 5 – Natural Gas Manifold Pressure Ranges
UNIT
MODEL
48TCD,S
48TCE,R
48TCF,T
48TCL
48TCM
48TCN
NA: Not Available
{ 3 Phase models only
UNIT
SIZE
All
All
HIGH
FIRE
3.5 in. wg
(872 Pa)
3.5 in. wg
(872 Pa)
LOW
FIRE
1.7 in. wg
(423 Pa){
NA
RANGE
2.0---5.0 in. wg (Hi)
(498---1245 Pa)
2.0---5.0 in. wg (Hi)
(498---1245 Pa)
Liquid Propane — Accessory packages are available for
field--installation that will convert the 48TC unit (except
low NO
model) to operate with Liquid Propane (LP)
x
fuels. These kits include new orifice spuds, new springs
for gas valves and a supply line low pressure switch. See
section on Orifice Replacement for details on orifice size
selections.
Low NO
models include specially--sized orifices and use
x
of different flue flow limits and tube baffles. Because of
these extra features, conversion of these models to LP is
not recommended.
Fuel line pressure entering unit gas valve must remain
within specified range.
C08238
Fig. 29 -- LP Low Pressure Switch (Installed)
C
PNK
LP LPS
GRA
NO
BRN
MGV
C
C08285
IGC
BRN
J2-11
IGC
J2-12
TSTAT
W2
Fig. 30 -- LP Supply Line Low Pressure Switch Wiring
23
This switch also prevents operation when the propane tank
level is low which can result in gas with a high
concentration of impurities, additives, and residues that
have settled to the bottom of the tank. Operation under
these conditions can cause harm to the heat exchanger
system. Contact your fuel supplier if this condition is
suspected.
Flue Gas Passageways
To inspect the flue collector box and upper areas of the
heat exchanger:
1. Remove the combustion blower wheel and motor assembly according to directions in Combustion--Air
Blower section. See Fig. 31.
2. Remove the flue cover to inspect the heat exchanger.
3. Clean all surfaces as required using a wire brush.
Combustion--Air Blower
48TC
Clean periodically to assure proper airflow and heating
efficiency.Inspectblowerwheeleveryfalland
periodically during heating season. For the first heating
season, inspect blower wheel bi--monthly to determine
proper cleaning frequency.
To access burner section, slide the sliding burner partition
out of the unit.
To inspect blower wheel, shine a flashlight into draft hood
opening. If cleaning is required, remove motor and wheel
as follows:
1. Slide burner access panel out.
2. Remove the 7 screws that attach induced--draft motor
housing to vestibule plate. (See Fig. 31.)
3. The blower wheel can be cleaned at this point. If additional cleaning is required, continue with Steps 4
and 5.
4. To remove blower from the motor shaft, remove 2
setscrews.
5. To remove motor, remove the 4 screws that hold the
motor to mounting plate. Remove the motor cooling
fan by removing one setscrew. Then remove nuts that
hold motor to mounting plate.
6. To reinstall, reverse the procedure outlined above.
Support
Insulation
Assembly
Wind Cap Assembly
(shown inverted,
as shipped)
Regulator
Bae Assembly
(Low NOx only)
Retainer
Regulator
Gasket
Seal Strips, Sponge Rubber
Inducer Fan-Motor
Assembly
Heater Tube
Assembly
Flue Bae
(Low NOx only)
Burner Assembly
C08227
Fig. 31 -- Heat Exchanger Assembly
24
Burners and Igniters
!
CAUTION
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in
equipment damage.
When working on gas train, do not hit or plug
orifice spuds.
Main Burners
To access burners, remove burner access panel and slide
out burner partition. At the beginning of each heating
season, inspect for deterioration or blockage due to
corrosion or other causes. Observe the main burner flames
and adjust, if necessary.
Orifice projection — Refer to Fig. 32 for maximum
projection dimension for orifice face to manifold tube.
Orifice
1.00-in
(25.4 mm)
8. Slide the burner tray out of the unit (Fig. 33).
9. To reinstall, reverse the procedure outlined above.
Cleaning and Adjustment
1. Remove burner rack from unit as described in Removal and Replacement of Gas Train section, above.
2. Inspect burners; if dirty, remove burners from rack.
(Mark each burner to identify its position before removing from the rack.)
3. Use a soft brush to clean burners and cross--over port
as required.
4. Adjust spark gap. (See Fig. 35 and Fig. 36.)
5. If factory orifice has been removed, check that each
orifice is tight at its threads into the manifold pipe
and that orifice projection does not exceed maximum
valve. See Fig. 32
6. Reinstall burners on rack in the same locations as
factory--installed. (The outside crossover flame regions of the outermost burners are pinched off to prevent excessive gas flow from the side of the burner
assembly. If the pinched crossovers are installed
between two burners, the flame will not ignite properly.)
RACEWAY
INTEGRATED GAS UNIT
CONTROLLER (IGC)
48TC
Manifold
Pipe
Fig. 32 -- Orifice Projection
Removal and Replacement of Gas Train
See Fig. 27, Fig. 31 and Fig. 33.
1. Shut off manual gas valve.
2. Shut off power to unit.
3. Slide out burner partition.
4. Disconnect gas piping at unit gas valve.
5. Remove wires connected to gas valve. Mark each
wire.
Fig. 33 -- Burner Tray Details
6. Remove igniter wires and sensor wires at the Integrated Gas Unit Controller (IGC). (See Fig. 34.)
7. Remove the 2 screws that attach the burner rack to
the vestibule plate (Fig. 31).
C08211
C06153
HOLE IN END PANEL (HIDDEN)
C08454
Fig. 34 -- Unit Control Box/IGC Location
7. Reinstall burner rack as described in Removal and
Replacement of Gas Train section, above.
Gas Valve — All three--phase models (except Low NO
are equipped with 2--stage gas valves. Single--phase
models and all Low NO
models are equipped with
x
single--stage gas valves. See Fig. 37 for locations of
adjustment screws and features on the gas valves.
To adjust gas valve pressure settings:
IMPORTANT: Leak check all gas connections including
the main service connection, gas valve, gas spuds, and
manifold pipe plug. All leaks must be repaired before
firing unit.
Check Unit Operation and Make Necessary Adjustments
NOTE: Gas supply pressure at gas valve inlet must be
within specified ranges for fuel type and unit size. See
Table 4 and Table 5.
)
x
25
1. Remove manifold pressure tap plug from manifold
and connect pressure gauge or manometer. (See Fig.
33.)
2. Turn on electrical supply.
3. Turn on unit main gas valve.
4. Set room thermostat to call for heat. If unit has two-stage gas valve, verify high--stage heat operation before attempting to adjust manifold pressure.
5. When main burners ignite, check all fittings, manifold, and orifices for leaks.
6. Adjust high--stage pressure to specified setting by
turning the plastic adjustment screw clockwise to increase pressure, counter--clockwise to decrease pressure.
7. For Two--Stage Gas Valves set room thermostat to
call for low--stage heat. Adjust low--stage pressure to
48TC
specified setting.
8. Replace regulator cover screw(s) when finished.
9. With burner access panel removed, observe unit heating operation in both high stage and low stage operation if so equipped. Observe burner flames to see if
they are blue in appearance, and that the flames are
approximately the same for each burner.
10. Turn off unit, remove pressure manometer and replace the 1/8 in. pipe fitting on the gas manifold. (See
Fig. 32.)
Switch
Limit
Remove blower access panel. Limit switch is located on
the fan deck. See Fig. 28.
Burner Ignition
Unit is equipped with a direct spark ignition 100% lockout
system. Integrated Gas Unit Controller (IGC) is located in
the control box. See Fig. 34. The IGC contains a
self--diagnostic LED (light--emitting diode). A single LED
(see Fig. 38) on the IGC provides a visual display of
operational or sequential problems when the power supply
is uninterrupted. When a break in power occurs, the IGC
will be reset (resulting in a loss of fault history) and the
indoor (evaporator) fan ON/OFF times will be reset. The
LED error code can be observed through the viewport.
During servicing refer to the label on the control box
cover or Table 8 for an explanation of LED error code
descriptions.
If lockout occurs, unit may be reset by interrupting power
supply to unit for at least 5 seconds.
* A 3---second pause exists between LED error code flashes. If.
more than one error code exists, all applicable codes will be
displayed in numerical sequence.
{ Indicates a code that is not an error. The unit will continue to
operate when this code is d isplayed.
ERROR CODE
DESCRIPTION
IMPORTANT: Refer to Troubleshooting Table 13 and
Table 14 for additional information.
Orifice Replacement
This unit uses orifice type LH32RFnnn (where nnn
indicates orifice reference size). When replacing unit
orifices, order the necessary parts via Carrier RCD. See
Table 10 for available orifice sizes. See Table 11 and
Table 12 for orifice sizes for Natural Gas and LP fuel
usage at various elevations above sea level.
Check that each replacement orifice is tight at its threads
into the manifold pipe and that orifice projection does not
exceed maximum value. See Fig. 32.
27
48TC
Single Stage
Red LED-Status
2 Stage
C08210
Fig. 37 -- Gas Valves
Fig. 38 -- Integrated Gas Control (IGC) Board
28
C08452
Table 9 – IGC Connections
TERMINAL LABELPOINT DESCRIPTIONSENSOR LOCATIONTYPE OF I/O
LEGEND
NG = Natural GasLP = Liquid Propane
* As the height above sea level increases, there is less oxygen
per cubic ft. of air. Therefore, heat input rate should be reduced
at higher altitudes.
{ Not included in kit. May be purchased separately through
dealer.
2
2
2
3
3
Minimum heating entering air temperature
When operating on first stage heating, the minimum
temperature of air entering the dimpled heat exchanger is
50_F continuous and 45_F intermittent for standard heat
exchangers and 40_F continuous and 35_ F intermittent for
stainless steel heat exchangers. To operate at lower
mixed--air temperatures, a field--supplied outdoor--air
thermostat must be used to initiate both stages of heat
when the temperature is below the minimum required
temperature to ensure full fire operation. Wire the
outdoor--air thermostat OALT (part no. HH22AG106) in
series with the second stage gas valve. See Fig. 39. Set the
outdoor--air thermostat at 35_F for stainless steel heat
exchangers or 45_F for standard heat exchangers. This
temperature setting will bring on the second stage of heat
whenever the ambient temperature is below the thermostat
setpoint. Indoor comfort may be compromised when
heating is initiated using low entering air temperatures
with insufficient heating temperature rise.
Thermostat
TH1
TH2
W1
OALT
W2
Fig. 39 -- OATL Connections
Troubleshooting Heating System
Referto Table 13and Table14 for additional
troubleshooting topics.
48TC
LCTB
W1
W2
C08442
31
Table 13 – Heating Service Analysis
PROBLEMCAUSEREMEDY
Misaligned spark electrodes.
No gas at main burners.
Burners Will Not Ignite.
48TC
Inadequate Heating.
Poor Flame
Characteristics.
Burners Will Not Turn
Off.
Water in gas line.Drain water and install drip leg to trap water.
No power to furnace.Check power supply, fuses, wiring, and circuit breaker.
No 24 v power supply to control
circuit.
Miswired or loose connections.Check all wiring and wire nut connections.
Burned ---out heat anticipator in
thermostat.
Broken thermostat wires.Run continuity check. Replace wires, if necessary.
Dirty air filter.Clean or replace filter as necessary.
Gas input to unit too low.
Unit undersized for application.Replace with proper unit or add additional unit.
Restricted airflow.Clean filter, replace filter, or remove any restrictions.
Blower speed too low.
Limitswitchcyclesmainburners.
Too much outdoor air.
Incomplete combustion (lack of
combustion air) results in:
Aldehyde odors, CO, sooting
flame, or floating flame.
Unit is locked into Heating mode
for a one minute minimum.
Check flame ignition and sensor electrode positioning.
Adjust as needed.
Check gas line for air, purge as necessary. After purging
gas line of air, allow gas to dissipate for at least 5 minutes
before attempting to relight unit.
Check gas valve.
Check transformer. Transformers with internal overcurrent
protection require a cool down period before resetting.
Replace thermostat.
Check gas pressure at manifold. Clock gas meter for input.
If too low, increase manifold pressure, or replace with
correct orifices.
Use high speed tap, increase fan speed, or install optional
blower, as suitable for individual units.
Check rotation of blower, thermostat heat anticipator
settings, and temperature rise of unit. Adjust as needed.
Adjust minimum position.
Check economizer operation.
Check all screws around flue outlets and burner
compartment. Tighten as necessary.
Cracked heat exchanger.
Overfired unit — reduce input, change orifices, or adjust
gas line or manifold pressure.
Check vent for restriction. Clean as necessary.
Check orifice to burner alignment.
Wait until mandator y one --- minute time period has elapsed
or reset power to unit.
32
Table 14 – IGC Board LED Alarm Codes
LED
FLASH
CODE
DESCRIPTION
ACTION TAKEN BY
CONTROL
RESET METHODPROBABLE CAUSE
OnNormal Operation———
Loss of power to the IGC. Check 5 amp
OffHardware FailureNo gas heating.—
fuse on IGC, power to unit, 24V circuit
break er, tra nsf or mer, a nd wir ing t o t he
IGC.
High temperature limit switch is open.
Check the operation of the indoor (evaporator) fan motor.
Ensure that the supply-air temperature
rise is within the range on the unit nameplate. Check wiring and limit switch opera-
2
Flashes
Limit Switch Fault
Gas valve and igniter
Off.
Indoor fan and inducer
On.
Limit switch closed,
or heat call (W) Off.
tion.
3
Flashes
4
Flashes
Flame Sense Fault
Four Consecutive Limit
Switch Fault
Indoor fan and inducer
On.
No gas heating.
Flame sense normal.
Power reset for LED
reset.
Heat call (W) Off.
Power reset for LED
reset.
The IGC sensed a flame when the gas
valve should be closed. Check wiring,
flame sensor, and gas valve operation.
4 consecutive limit switch faults within a
single call for heat. See Limit Switch Fault.
Unit unsuccessfully attempted ignitio n for
15 minutes. Check igniter and flame sen-
5
Flashes
Ignition FaultNo gas heating.
Heat call (W) Off.
Power reset for LED
reset.
sor electrode spacing, gaps, etc. Check
flame sense and igniter wiring. Check gas
valve operation and gas supply. Check
gas valve connections to IGC terminals.
BRN lead must be on Pin 11.
Inducer sense On when heat call Off, or
inducer sense Off when heat call On.
Check wiring, voltage, and operation of
IGC motor. Check speed sensor wiring to
IGC.
Rollout switch has opened. Check gas
valve operation. Check induced-draft
blower wheel is properly secured to motor
shaft.
IGC has sensed internal hardware or software error. If fault is not cleared by resetting 24 v power, replace the IGC.
Electrical interference is disrupting the
IGC software.
6
Flashes
Induced Draft Motor
Fault
If heat off: no gas
heating.
If heat on: gas valve
Off and inducer On.
Inducer sense normal, or heat call (W)
Off.
Gas valve and igniter
7
Flashes
Rollout Switch Lockout
Off.
Indoor fan and inducer
Power reset.
On.
8
Flashes
Flashes
LEGEND
IGC --- Integrated Gas Unit Control
LED --- L i g ht --- E m i t t i n g D i o d e
NOTES:
Internal Control LockoutNo gas heating.Power reset.
9
Temporary Software
Lockout
1. There is a 3 --- second pause between alarm code displays.
2. If more than one alarm code exists, all applicable alarm codes will be displayed in numerical sequence.
3. Alarm codes on the IGC will be lost if power to the unit is interrupted.
No gas heating.
1 hour auto reset, or
power reset.
48TC
33
48TC
C08199
Fig. 40 -- PremierLink Controller
PREMIERLINKT CONTROL
The PremierLink controller (see Fig. 40) is compatible
with Carrier Comfort Networkr (CCN) devices. This
control is designed to allow users the access and ability to
change factory--defined settings, thus expanding the
function of the standard unit control board. CCN service
access tools include System Pilot (TM), Touch Pilot (TM)
and Service Tool. (Standard tier display tools Navigatort
and Scrolling Marquee are not suitable for use with latest
PremierLink controller (Version 2.x).)
The PremierLink control is factory--mounted in the 48TC
unit’s main control box to the left of the LCTB. Factory
wiring is completed through harnesses connected to the
LCTB thermostat. Field connections are made at a
16--pole terminal block (TB1) located on the bottom shelf
of the unit control box in front of the PremierLink
controller The factory--installed PremierLink control
includes the supply--air temperature (SAT) sensor. The
outdoor air temperature (OAT) sensor is included in the
FIOP/accessory EconoMi$er 2 package.
Refer to Fig. 40 for PremierLink connection locations.
NOTE:Refer to Form 33CS--58SI for complete
PremierLink configuration, operating sequences and
troubleshooting information. Have a copy of this manual
available at unit start--up.
The PremierLink controller requires the use of a Carrier
electronic thermostat or a CCN connection for time
broadcast to initiate its internal timeclock. This is
necessary for broadcast of time of day functions
(occupied/unoccupied).
NOTE:PremierLink controller is shipped in Sensor
mode. To be used with a thermostat, the PremierLink
controller must be configured to Thermostat mode. Refer
to PremierLink Configuration instructions for Operating
Mode.
SupplyAirTemperature(SAT)Sensor—On
FIOP--equipped 48TC unit, the unit is supplied with a
supply--air temperature (SAT) sensor (33ZCSENSAT).
This sensor is a tubular probe type, approx 6--inches (12.7
mm) in length. It is a nominal 10--k ohm thermistor. See
Table 15 for temperature--resistance characteristic.
The SAT is factory--wired. The SAT probe is wire--tied to
the supply--air opening (on the horizontal opening end) in
its shipping position. Remove the sensor for installation.
Re--position the sensor in the flange of the supply--air
opening or in the supply air duct (as required by local
codes). Drill or punch a 1/2--in. hole in the flange or duct.
Use two field--supplied, self--drilling screws to secure the
sensor probe in a horizontal orientation. See Fig. 41.
SUPPLY AIR
TEMPERATURE
SENSOR
SUPPLY AIR
RETURN AIR
ROOF
CURB
C08200
Fig. 41 -- Typical Mounting Location for Supply Air
Temperature (SAT) Sensor on Small Rooftop Units
34
C08248
48TC
Fig. 42 -- PremierLink Wiring Schematic
35
Table 15 – Thermistor Resistance vs Temperature
Values for Space Temperature Sensor, Supply Air
NOTE:The sensor must be mounted in the discharge
airstream downstream of the cooling coil and any heating
devices. Be sure the probe tip does not come in contact
with any of the unit’s heater surfaces.
Outdoor Air Temperature (OAT) Sensor — The OAT is
factory--mounted in theEconoMi$er2(FIOP or
accessory). It is a nominal 10k ohm thermistor attached to
aneyeletmountingring.SeeTable15for
temperature--resistance characteristic.
Field connections — Field connections for accessory
sensor and input devices are made at the 16--pole terminal
block (TB1) located on the control box bottom shelf in
front of the PremierLink control. Some input devices also
require a 24--vac signal source; connect at LCTB terminal
R at “THERMOSTAT” connection strip for this signal
source. See connections figures on following pages for
field connection locations (and for continued connections
at the PremierLink board inputs).
Table 17 provides a summary of field connections for
units equipped with Space Sensor. Table 18 provides a
summary of field connections for units equipped with
Space Thermostat.
SpaceSensors--ThePremierLinkcontrolleris
factory--shipped configured for Space Sensor Mode. A
Carrier T--55 or T--56 space sensor must be used. T--55
space temperature sensor provides a signal of space
temperature to the PremierLink control T--56 provides
same space temperature signal plus it allows for
adjustment of space temperature setpoints from the face of
the sensor by the occupants. See Table 15 for temperature
versus resistance characteristic on the space sensors.
Connect T--55 -- See Fig. 43 for typical T--55 internal
connections. Connect the T--55 SEN terminals to TB1
terminals 1 and 3 (see Fig. 44).
2
SW1
3
45
SEN
61
RED(+)
WHT(GND)
BLK(-)
BRN (GND)
BLU (SPT)
CCN COM
SENSOR WIRING
EconoMi$er 2 — The PremierLink control is used with
EconoMi$er 2 (option or accessory) for outdoor air
management. The damper position is controlled directly
by the PremierLink control; EconoMi$er 2 has no internal
logic device.
Outdoor air management functions can be enhanced with
field--installation of these accessory control devices:
Enthalpy control (outdoor air or differential sensors)
Space CO
Outdoor air CO
sensor
2
sensor
2
Refer to Table 16 for accessory part numbers.
Fig. 43 -- T--55 Space Temperature Sensor Wiring
TB1PL
SENJ6-7
SEN
1
3
Fig. 44 -- PremierLink T--55 Sensor
36
C08201
J6-6
C08212
Table 16 – PremierLink Sensor Usage
APPLICATION
OUTDOOR AIR
TEMPERATURE
SENSOR
RETURN AIR
TEMPERATURE
SENSOR
OUTDOOR AIR
ENTHALPY SENSOR
Differential Dry Bulb
Tempe r atu r e w ith
PremierLink
(PremierLink requires
I n c l u d e d ---
CRTEMPSN001A00
R e q u i r e d ---
33ZCT55SPT
or equivalent
------
4---20 mA Actuator)
Single Enthalpy with
PremierLink
(PremierLink requires
I n c l u d e d ---
Not Used
---
4 --- 20mA A c t u ator)
Differential Enthalpy
with PremierLink
(PremierLink requires
I n c l u d e d ---
Not Used
---
4 --- 20mA A c t u ator)
NOTES:
CO
Sensors (Optional):
2
33ZCSENCO2 --- Room sensor (adjustable). Aspirator box is required for duct mounting of the sensor.
33ZCASPCO2 --- Aspirator box used for duct---mounted CO
33ZCT55CO2 --- Space temperature and CO
33ZCT56CO2 --- Space temperature and CO
9IAQ---SENAnalog, 4 --- 20mA
10FILTERDiscrete, 24VAC
11I A Q --- C O M / O AQ --- C O M/ R H --- CO MAnalog, 4---20mA
12CCN + (RED)Digital,,5VDC
13O A Q --- S E N / R H --- S E NAnalog, 4---20mA
14CCN Gnd (WHT)Digital, 5VDC
15AUX OUT(Power Exhaust)(Output)Discrete 24VAC
16CCN --- (BLK)Digital, 5VDC
LEGEND:
T55--- Space Temperature Sensor
T56--- Space Temperature Sensor
CCN--- Carrier Comfort Network (communication bus)
CMPSAFE--- Compressor Safety
FILTER--- Dirty Filter Switch
F S D--- F i r e Shutd o w n
IAQ--- Indoor Air Quality (CO
OAQ--- Outdoor Air Quality (CO
RH--- Relative Humidity
9I A Q --- S E NA n a l o g , 4 --- 2 0 m A
10W2Discrete, 24VAC
11I A Q --- C O M /OA Q --- CO M / R H --- C O MA nalog, 4 --- 2 0 m A
12CCN + (RED)Digital, 5VDC
13O A Q --- S E N / R H --- S E NA nalog, 4 --- 2 0 m A
14CCN Gnd (WHT)Digital, 5VDC
15AUX OUT (Power Exhaust)(Output) Discrete 24VAC
16CCN --- (BLK)Digital, 5VDC
LEGEND:
48TC
CCN---Carrier Comfort Network (communication bus)
G---T h e r mo s t a t Fa n
IAQ---Indoor Air Quality (CO
OAQ---Outdoor Air Quality (CO
RAT---Return Air Temperature
Connect T--56--See Fig.45 for T--56 internal
connections. Install a jumper between SEN and SET
terminals as illustrated. Connect T--56 terminals to TB1
terminals 1, 3 and 5 (see Fig. 46).
2
SW1
CoolWarm
3
45
SEN
61
RED(+)
WHT(GND)
BLK(-)
SET
BRN (GND)
BLU (SPT)
BLK
(T56)
CCN COM
SENSOR WIRING
JUMPER
TERMINALS
AS SHOWN
C08202
Fig. 45 -- T--56 Internal Connections
TB1PL
SENJ6-7
SEN
Jumper
SET
SET
1
TB1
3
5
PL
J6-6
J6-5
C08213
Fig. 46 -- PremierLink T--56 Sensor
Connect Thermostat — A 7--wire thermostat connection
requires a 24--v power source and a common connection.
Use the R and C terminals on the LCTB’s THERMOSTAT
connection strip for these. Connect the thermostat’s Y1,
Y2, W1, W2 and G terminals to PremierLink TB1 as
shown in Fig. 47.
SPACE
THERMOSTAT
R
GJ4-12
Y1
Y2
W1
W2
C
LCTB
THERMOSTAT
R
TB1
2
4
6
8
10
LCTB
C
PL
J4-10
J4-8
J4-6
J4-4
THERMOSTAT
C08119
Fig. 47 -- Space Thermostat Connections
If the 48TC unit has an economizer system and
free--cooling operation is required, a sensor representing
ReturnAir Temperature mustalsobe connected
(field--supplied and installed). This sensor may be a T--55
Space Sensor (see Fig. 43) installed in the space or in the
return duct, or it may be sensor PNO 33ZCSENSAT,
installed in the return duct. Connect this sensor to TB1--1
andTB1--3perFig.44.Temperature--resistance
characteristic is found in Table 15.
Configure the unit for Thermostat Mode — Connect to the
CCN bus using a CCN service tool and navigate to
38
PremierLink Configuration screen for Operating Mode.
Default setting is Sensor Mode (value 1). Change the
value to 0 to reconfigure the controller for Thermostat
Mode.
When the PremierLink is configured for Thermostat
Mode, these functions are not available: Fire Shutdown
(FSD), Remote Occupied (RMTOCC), Compressor Safety
(CMPSAFE), Supply Fan Status (SFS), and Filter Pressure
Switch (FILTER).
Economizer controls —
Outdoor Air Enthalpy Control (PNO HH57AC077) --
The enthalpy control (HH57AC077) is available as a
field--installed accessory to be used with the EconoMi$er2
damper system. The outdoor air enthalpy sensor is part of
theenthalpycontrol.(Theseparatefield--installed
accessory return air enthalpy sensor (HH57AC078) is
required for differential enthalpy control. See below.)
Locate the enthalpy control in the economizer hood.
Locate two GRA leads in the factory harness and connect
these leads to enthalpy control sensors 2 and 3. See Fig.
48. Connect the enthalpy control power input terminals to
economizer actuator power leads RED (connect to TR)
and BLK (connect to TR1).
The outdoor enthalpy changeover setpoint is set at the
enthalpy controller.
The enthalpy control receives the outdoor air enthalpy
from the outdoor air enthalpy sensor and provides a dry
contact switch input to the PremierLink controller. A
closed contact indicates that outside air is preferred to the
return air. An open contact indicates that the economizer
should remain at minimum position.
Differential Enthalpy Control — Differential enthalpy
control is provided by sensing and comparing the outside
air and return air enthalpy conditions. Install the outdoor
air enthalpy control as described above. Add and install a
return air enthalpy sensor.
Return Air Enthalpy Sensor — Mount the return--air
enthalpy sensor (HH57AC078) in the return--air duct. The
return air sensor is wired to the enthalpy controller
(HH57AC077). See Fig. 49.
ENTHALPY CONTROLLER
B
TRTR1
C
A
D
SO
SR
2
LED
NOTES:
1. Remove factory-installed jumper across SR and + before connecting
wires from return air sensor.
2. Switches shown in high outdoor air enthalpy state. Terminals 2 and 3
close on low outdoor air enthalpy relative to indoor air enthalpy.
3. Remove sensor mounted on back of control and locate in outside airstream.
RED
BRN
BLK
+
+
3
1
RED
GRAY/ORN
GRAY/RED
WIRE HARNESS
IN UNIT
(OUTDOOR
S
AIR
+
ENTHALPY
SENSOR)
S
(RETURN AIR
ENTHALPY
+
SENSOR)
C06019
Fig. 49 -- Outside and Return Air Enthalpy Sensor
Wiring
To wire the return air enthalpy sensor, perform the
following:
1. Use a 2--conductor, 18 or 20 AWG, twisted pair cable
to connect the return air enthalpy sensor to the enthalpy controller.
2. At the enthalpy control remove the factory--installed
resistor from the (SR) and (+) terminals.
3. Connect the field--supplied RED wire to (+) spade
connector on the return air enthalpy sensor and the
(SR+) terminal on the enthalpy controller. Connect
the BLK wire to (S) spade connector on the return air
enthalpy sensor and the (SR) terminal on the enthalpy
controller.
NOTE:The enthalpy control must be set to the “D”
setting for differential enthalpy control to work properly.
The enthalpy control receives the indoor and return
enthalpy from the outdoor and return air enthalpy sensors
and providesa dry contact switch inputto the
PremierLink controller. A closed contact indicates that
outside air is preferred to the return air. An open contact
indicates that the economizer should remain at minimum
position.
Indoor Air Quality (CO
sensor) — The indoor air quality
2
sensor accessory monitors space carbon dioxide (CO
levels. This information is used to monitor IAQ levels.
Several types of sensors are available, for wall mounting
in the space or in return duct, with and without LCD
display, and in combination with space temperature
sensors. Sensors use infrared technology to measure the
levels of CO
The CO
present in the space air.
2
sensors are all factory set for a range of 0 to
2
2000 ppm and a linear mA output of 4 to 20. Refer to the
instructions supplied with the CO
sensor for electrical
2
48TC
)
2
39
requirements and terminal locations. See Fig. 50 for
typical CO
HG
+
-
sensor wiring schematic.
2
24 VAC
OR
24 VDC
2
1
8
+
0-10VDC
-
SIG COM (J4-6)
+
4-20mA (J4-5)
NC
COM
NO
5
1
4
32
7
6
48TC
Fig. 50 -- Indoor/Outdoor Air Quality (CO2)Sensor
(33ZCSENCO2) -- Typical Wiring Diagram
ALARM
RELAY
}
CONTACTS
C07134
Refer to Form 33CS--58SI, PremierLink Installation,
Start--up, and Configuration Instructions, for detailed
configuration information
Outdoor Air Quality Sensor (PNO 33ZCSENCO2 plus
weatherproof enclosure) — The outdoor air CO
designed to monitor carbon dioxide (CO
sensor is
2
) levels in the
2
outside ventilation air and interface with the ventilation
damper in an HVAC system. The OAQ sensor is packaged
with an outdoor cover. See Fig. 52. The outdoor air CO
sensor must be located in the economizer outside air hood.
2
To accurately monitor the quality of the air in the
conditioned air space, locate the sensor near a return--air
grille (if present) so it senses the concentration of CO
leaving the space. The sensor should be mounted in a
location to avoid direct breath contact.
Do not mount the IAQ sensor in drafty areas such as near
supply ducts, open windows, fans, or over heat sources.
Allow at least 3 ft (0.9 m) between the sensor and any
corner. Avoid mounting the sensor where it is influenced
by the supply air; the sensor gives inaccurate readings if
the supply air is blown directly onto the sensor or if the
supply air does not have a chance to mix with the room air
before it is drawn into the return airstream.
Wiring the Indoor Air Quality Sensor —
For each sensor, use two 2--conductor 18 AWG (American
Wire Gage) twisted--pair cables (unshielded) to connect
the separate isolated 24 vac power source to the sensor
and to connect the sensor to the control board terminals.
To connect the sensor to the control, identify the positive
(4 to 20 mA) and ground (SIG COM) terminals on the
sensor. See Fig. 50. Connect the 4--20 mA terminal to
terminal TB1--9 and connect the SIG COM terminal to
terminal TB1--7. See Fig. 51.
IAQ Sensor
SENJ5-5
COM
24 VAC
TB1
9
TB1
7
PL
J5-6
C08274
Fig. 51 -- Indoor CO2Sensor (33ZCSENCO2)
Connections
COVER REMOVEDSIDE VIEW
2
Fig. 52 -- Outdoor Air Quality Sensor Cover
Wiring the Outdoor Air CO
Sensor — A dedicated power
2
supply is required for this sensor. A two--wire cable is
required to wire the dedicated power supply for the sensor.
The two wires should be connected to the power supply
and terminals 1 and 2.
To connect the sensor to the control, identify the positive
(4 to 20 mA) and ground (SIG COM) terminals on the
OAQ sensor. See Fig. 50. Connect the 4 to 20 mA
terminal to 48TC’s terminal TB1--11. Connect the SIG
COM terminal to 48TC’s terminal TB1--13. See Fig. 53.
OAQ Sensor/RH Sensor
SENJ5-2
COM
24 VAC
TB1
13
TB1
11
Fig. 53 -- Outdoor CO2Sensor Connections
Refer to Form 33CS--58SI, PremierLink Installation,
Start--up, and Configuration Instructions, for detailed
configuration information.
Smoke Detector/Fire Shutdown (FSD) — This function is
available only when PremierLink is configured for
(Space) Sensor Mode. The unit is factory--wired for
PremierLinkFSD operationwhenPremierLinkis
factory--installed.
On 48TC units equipped with factory--installed Smoke
Detector(s), the smoke detector controller implements the
C07135
PL
J5-3
C08275
40
unit shutdown through its NC contact set connected to the
unit’s LCTB input. The FSD function is initiated via the
smoke detector’s Alarm NO contact set. The PremierLink
communicates the smoke detector’s tripped status to the
CCN building control. See Fig. 23 for unit smoke detector
wiring.
Fan (Pressure) Switch (NO, close on rise in pressure)
LCTB
Thermostat
R
TB1
8
PL
J4-6
Alarm state is reset when the smoke detector alarm
condition is cleared and reset at the smoke detector in the
unit.
Filter Status Switch — This function is available only
when PremierLink is configured for (Space) Sensor Mode.
PremierLink control can monitor return filter status in two
ways: By monitoring a field--supplied/installed filter
pressure switch or via supply fan runtime hours.
Using switch input: Install the dirty filter pressure switch
according to switch manufacturer’s instructions, to
measure pressure drop across the unit’s return filters.
Connect one side of the switch’s NO contact set to
LCTB’s THERMOSTAT--R terminal. Connect the other
side of the NO contact set to TB1--10. Setpoint for Dirty
Filter is set at the switch. See Fig. 54.
Filter Switch (NO, close on rising pressure (high drop))
LCTB
Thermostat
R
TB1
10
PL
J4-4
C08216
Fig. 54 -- PremierLink Filter Switch Connection
When the filter switch’s NO contact set closes as filter
pressure drop increases (indicating dirt--laden filters), the
input signal to PremierLink causes the filter status point to
read “DIRTY”.
Using Filter Timer Hours: Refer to Form 33CS--58SI for
instructions on using the PremierLink Configuration
screens and on unit alarm sequence.
Supply Fan Status Switch — The PremierLink control can
monitorsupplyfanoperationthrougha
field--supplied/installed differential pressure switch. This
sequence will prevent (or interrupt) operation of unit
cooling, heating and economizer functions until the
pressure switch contacts are closed indicating proper
supply fan operation.
Install the differential pressure switch in the supply fan
section according to switch manufacturer’s instructions.
Arrange the switch contact to be open on no flow and to
close as pressure rises indicating fan operation.
Connect one side of the switch’s NO contact set to
LCTB’s THERMOSTAT--R terminal. Connect the other
side of the NO contact set to TB1--8. Setpoint for Supply
Fan Status is set at the switch. See Fig. 55.
C08118
Fig. 55 -- PremierLink Wiring Fan Pressure Switch
Connection
Remote Occupied Switch — The PremierLink control
permits a remote timeclock to override the control’s
on--board occupancy schedule and place the unit into
Occupied mode. This function may also provide a “Door
Switch” time delay function that will terminate cooling
and heating functions after a 2--20 minute delay.
Connect one side of the NO contact set on the timeclock
to LCTB’s THERMOSTAT--R terminal. Connect the other
side of the timeclock contact to the unit’s TB1--2 terminal.
Remote Occupied
Time Clock
LCTB
Thermostat
R
TB1
2
PL
J4-12
C08214
Fig. 56 -- PremierLink Wiring Remote Occupied
Refer to Form 33CS--58SI for additional information on
configuring the PremierLink control for Door Switch
timer function.
Power Exhaust (output) -- Connect the accessory Power
Exhaust contactor coils(s) per Fig. 57.
Power Exhaust
PEC
TAN
TB1
15
PL
J8-3
LCTB
THERMOSTAT
GRA
C
C08120
Fig. 57 -- PremierLink Power Exhaust Output
Connection
Space Relative Humidity Sensor — The RH sensor is not
used with 48TC models at this time.
CCN Communication Bus — The PremierLink controller
connects to the bus in a daisy chain arrangement.
Negative pins on each component must be connected to
respective negative pins, and likewise, positive pins on
each component must be connected to respective positive
pins. The controller signal pins must be wired to the signal
ground pins. Wiring connections for CCN must be made
at the 3--pin plug.
48TC
41
At any baud (9600, 19200, 38400 baud), the number of
controllers is limited to 239 devices maximum. Bus length
may not exceed 4000 ft, with no more than 60 total
devices on any 1000--ft section. Optically isolated RS--485
repeaters are required every 1000 ft.
NOTE: Carrier device default is 9600 band.
COMMUNICATION BUS WIRE SPECIFICATIONS —
The CCN Communication Bus wiring is field--supplied
and field--installed. It consists of shielded 3--conductor
cable with drain (ground) wire. The cable selected must
be identical to the CCN Communication Bus wire used for
the entire network.
See Table 19 for recommended cable.
Table 19 – Recommended Cables
MANUFACTURERCABLE PART NO.
48TC
Alpha2413 or 5463
AmericanA22503
Belden8772
Columbia02525
NOTE: Conductors and drain wire must be at least 20
AWG, stranded, and tinned copper. Individual conductors
must be insulated with PVC, PVC/nylon, vinyl, Teflon, or
polyethylene. An aluminum/polyester 100% foil shield
and an outer jacket of PVC, PVC/nylon, chrome vinyl, or
Teflon with a minimum operating temperature range of
--20 C to 60 C is required. Do not run communication wire
in the same conduit as or next to any AC voltage wiring.
The communication bus shields must be tied together at
each system element. If the communication bus is entirely
within one building, the resulting continuous shield must
be connected to ground at only one single point. If the
communication bus cable exits from one building and
enters another building, the shields must be connected to
the grounds at a lightning suppressor in each building (one
point only).
Connecting CCN bus:
NOTE: When connecting the communication bus cable,
acolorcodesystem fortheentirenetwork is
recommended to simplify installation and checkout. See
Table 20 for the recommended color code.
Table 20 – Color Code Recommendations
Connect the CCN (+) lead (typically RED) to the units
TB1--12 terminal. Connect the CCN (ground) lead
(typically WHT) to the unit’s TB1--14 terminal. Connect
the CCN (--) lead (typically BLK) to the unit’s TB1--16
terminal. See Fig. 58.
CCN Bus
+ (RED)
GND (WHT)
– (BLK)
TB1
12
TB1
14
TB1
16
PL
J2-1
J2-2
J2-3
C08276
Fig. 58 -- PremierLink CCN Bus Connections
RTU--MP CONTROL SYSTEM
The RTU--MP controller, see Fig. 59, provides expanded
stand--aloneoperation oftheHVACsystem plus
connection and control through communication with
several Building Automation Systems (BAS) through
popular third--party network systems. The available
network systems are BACnet MP/TP, Modbus and
Johnson J2. Communication with LonWorks is also
possible by adding an accessory interface card to the
RTU--MP. Selection of the communication protocol and
baud rate are made at on--board DIP switches.
Carrier’s diagnostic display tools BACviewer6 Handheld
and Virtual BACview (loaded on a portable PC) must be
used with the RTU--MP controller. Connection to the
RTU--MP board is at the J12 access port, see Fig. 59.
The RTU--MP control is factory--mounted in the 48TC
unit’s main control box, to the left of the LCTB. See Fig.
60. Factory wiring is completed through harnesses
connected to the LCTB. Field connections for RTU--MP
sensors will be made at the Phoenix connectors on the
RTU--MP board. The factory--installed RTU--MP control
includes the supply--air temperature (SAT) sensor. The
outdoor air temperature (OAT) sensor is included in the
FIOP/accessory EconoMi$er 2 package.
Refer to Table 21, RTU--MP Controller Inputs and Outputs
for locations of all connections to the RTU--MP board.
SIGNAL TYPE
+Red1
GroundWhite2
---Black3
CCN BUS WIRE
COLOR
CCN PLUG PIN
NUMBER
42
Fig. 59 -- RTU--MP Multi--Protocol Control Board
48TC
C07129
43
48TC
C08458
44
Fig. 60 -- RTU--MP System Control Wiring Diagram
44
Table 21 – RTU--MP Controller Inputs and Outputs
POINT NAME
Space Temperature SensorsptsensAI (10K Thermistor)J 2 0 --- 1 , 2
Supply Air TemperaturesatAI (10K Thermistor)J 2 --- 1 , 2
Local Outside Air Temperature SensoroatsensAI (10K Thermistor)J 2 --- 3 , 4
Space Temperature Offset PotsptopotAI (100K Potentiometer)J 2 0 --- 3
Indoor Air QualityiaqA I (4 --- 2 0 ma)J 4 --- 2 , 3
Outdoor Air QualityoaqAI ( 4 --- 2 0 m a )J 4 --- 5 , 6
Safety Chain FeedbacksafetyDI (24 VAC)J 1 --- 9
Compressor SafetycompstatDI (24 VAC)J 1 --- 2
Fire ShutdownfiredownDI (24 VAC)J 1 --- 1 0
Enthalpy SwitchenthalpyDI (24 VAC)J 2 --- 6 , 7
Humidistat Input StatushumstatDI (24 VAC)J 5 --- 7 , 8
Space Relative HumiditysprhA I (4 --- 2 0 ma )
Outside Air Relative HumidityoarhA I (4 --- 2 0 ma)
Supply Fan StatusfanstatDI (24 VAC)
Filter StatusfiltstatDI (24 VAC)
Remote Occupancy InputremoccDI (24 VAC)
LEGEND
AI --- A n a log I n p ut
AO --- A n a l o g Ou tp u t
DI --- D i s c r e t e I n p ut
DO --- Discrete Output
* These inputs (if installed) take the place of the default input on the specific channel according to schematic.
P a r a l l e l p i n s J 5 --- 1 = J 2 --- 6, J 5 --- 3 = J 1 --- 1 0 , J 5 --- 5 = J1 --- 2 a r e u se d f or f i e l d --- i n s t a l l a t i o n .
Refer to the input configuration and accessory sections for more detail.
BACnet OBJECT
NAME
INPUTS
CONFIGURABLE INPUTS*
OUTPUTS
TYPE OF I/O
CONNECTION PIN
NUMBERS
J4---2,3 or J4---5,6
J 5 --- 1,2 o r J5 --- 3 , 4 or
J5 5,6 or J5--- 7,8
48TC
NOTE:Refer to Form 48--50H--T--2T for complete
configuration of RTU--MP, operating sequences and
troubleshooting information. Refer to RTU--MP 3rd PartyIntegration Guide for details on configuration and
troubleshooting of connected networks. Have a copy of
these manuals available at unit start--up.
The RTU--MP controller requires the use of a Carrier
space sensor. A standard thermostat cannot be used with
the RTU--MP system.
SupplyAirTemperature(SAT)Sensor--On
FIOP--equipped 48TC unit, the unit is supplied with a
supply--air temperature (SAT) sensor (33ZCSENSAT).
This sensor is a tubular probe type, approx 6--inches (12.7
mm) in length. It is a nominal 10--k ohm thermistor. See
Table 15 for temperature--resistance characteristic.
The SAT is factory--wired. The SAT probe is wire--tied to
the supply--air opening (on the horizontal opening end) in
its shipping position. Remove the sensor for installation.
Re--position the sensor in the flange of the supply--air
opening or in the supply air duct (as required by local
codes). Drill or punch a 1/2--in. hole in the flange or duct.
Use two field--supplied, self--drilling screws to secure the
sensor probe in a horizontal orientation. See Fig. 41.
Outdoor Air Temperature (OAT) Sensor -- The OAT is
factory--mounted in theEconoMi$er2(FIOP or
accessory). It is a nominal 10k ohm thermistor attached to
aneyeletmountingring.SeeTable15for
temperature--resistance characteristic.
EconoMi$er 2 -- The RTU--MP control is used with
EconoMi$er2 (option or accessory) for outdoor air
management. The damper position is controlled directly
by the RTU--MP control; EconoMi$er 2 has no internal
logic device.
Outdoor air management functions can be enhanced with
field--installation of these accessory control devices:
Enthalpy control (outdoor air or differential sensors)
Space CO
Outdoor air CO
sensor
2
sensor
2
Field Connections -- Field connections for accessory
sensors and input devices are made the RTU--MP, at plugs
J1, J2, J4, J5, J11 and J20. All field control wiring that
45
connects to the RTU--MP must be routed through the
raceway built into the corner post as shown in Fig. 34.
The raceway provides the UL required clearance between
high-- and low--voltage wiring. Pass the control wires
through the hole provided in the corner post, then feed the
wires thorough the raceway to the RTU--MP. Connect to
the wires to the removable Phoenix connectors and then
reconnect the connectors to the board.
terminal (BRN) to J20--2. Connect the SET terminal (STO
or BLK) to J20--3.
BRN (COM)
BLK (STO)
BLU (SPT)
SENSOR
WIRING
Space Temperature (SPT) Sensors
A field--supplied Carrier space temperature sensor is
required with the RTU--MP to monitor space temperature.
There are 3 sensors available for this application:
S 33ZCT55SPT, space temperature sensor with override
button
S 33ZCT56SPT, space temperature sensor with override
button and setpoint adjustment
48TC
S 33ZCT59SPT, space temperature sensor with LCD
(liquid crystal display) screen, override button, and
setpoint adjustment
Use 20 gauge wire to connect the sensor to the controller.
The wire is suitable for distances of up to 500 ft. Use a
three--conductor shielded cable for the sensor and setpoint
adjustmentconnections.If thesetpoint adjustment
(slidebar) is not required, then an unshielded, 18 or 20
gauge, two--conductor, twisted pair cable may be used.
Connect T--55 -- See Fig. 43 for typical T--55 internal
connections.Connect theT--55 SEN terminals to
RTU--MP J20--1 and J20--2. See Fig. 61.
SEN
SEN
Fig. 61 -- RTU--MP T--55 Sensor Connections
Connect T--56--See Fig.45 for T--56 internal
connections. Install a jumper between SEN and SET
terminals as illustrated. Connect T--56 terminals to
RTU--MP J20--1, J20--2 and J20--3 per Fig. 62.
SENJ20-1
SEN
Jumper
SET
J20-1
J20-2
J20-2
C08460
ORSET SEN
OPB C OM- PW R+
POWER
24 VAC
NOTE: Must use a separate isolated transformer.
WIRING
C07132
Fig. 63 -- Space Temperature Sensor Typical Wiring
(33ZCT59SPT)
Economizer controls —
Outdoor Air Enthalpy Control (PNO HH57AC077) --
The enthalpy control (HH57AC077) is available as a
field--installed accessory to be used with the EconoMi$er2
damper system. The outdoor air enthalpy sensor is part of
theenthalpycontrol.(Theseparatefield--installed
accessory return air enthalpy sensor (HH57AC078) is
required for differential enthalpy control. See below.)
Locate the enthalpy control in the economizer hood.
Locate two GRA leads in the factory harness and connect
these leads to enthalpy control sensors 2 and 3. See Fig.
48. Connect the enthalpy control power input terminals to
economizer actuator power leads RED (connect to TR)
and BLK (connect to TR1).
The outdoor enthalpy changeover setpoint is set at the
enthalpy controller.
The enthalpy control receives the outdoor air enthalpy
from the outdoor air enthalpy sensor and provides a dry
contact switch input to the RTU--MP controller. A closed
contact indicates that outside air is preferred to the return
air. An open contact indicates that the economizer should
remain at minimum position.
SET
J20-3
C08461
Fig. 62 -- RTU--MP T--56 Sensor Connections
Connect T--59 -- The T--59 space sensor requires a
separate, isolated power supply of 24 VAC. See Fig. 61
for internal connections at the T--59. Connect the SEN
terminal (BLU) to RTU--MP J20--1. Connect the COM
Differential Enthalpy Control — Differential enthalpy
control is provided by sensing and comparing the outside
air and return air enthalpy conditions. Install the outdoor
air enthalpy control as described above. Add and install a
return air enthalpy sensor.
Return Air Enthalpy Sensor — Mount the return--air
enthalpy sensor (HH57AC078) in the return--air duct. The
46
return air sensor is wired to the enthalpy controller
(HH57AC077). See Fig. 49.
To wire the return air enthalpy sensor, perform the
following:
1. Use a 2--conductor, 18 or 20 AWG, twisted pair cable
to connect the return air enthalpy sensor to the enthalpy controller.
2. At the enthalpy control remove the factory--installed
resistor from the (SR) and (+) terminals.
3. Connect the field--supplied RED wire to (+) spade
connector on the return air enthalpy sensor and the
(SR+) terminal on the enthalpy controller. Connect
the BLK wire to (S) spade connector on the return air
enthalpy sensor and the (SR) terminal on the enthalpy
controller.
NOTE:The enthalpy control must be set to the “D”
setting for differential enthalpy control to work properly.
The enthalpy control receives the indoor and return
enthalpy from the outdoor and return air enthalpy sensors
and provides a dry contact switch input to the RTU--MP
controller. A closed contact indicates that outside air is
preferred to the return air. An open contact indicates that
the economizer should remain at minimum position.
Indoor Air Quality (CO
sensor) — The indoor air quality
2
sensor accessory monitors space carbon dioxide (CO
levels. This information is used to monitor IAQ levels.
Several types of sensors are available, for wall mounting
in the space or in return duct, with and without LCD
display, and in combination with space temperature
sensors. Sensors use infrared technology to measure the
levels of CO
The CO
present in the space air.
2
sensors are all factory set for a range of 0 to
2
2000 ppm and a linear mA output of 4 to 20. Refer to the
instructions supplied with the CO
sensor for electrical
2
requirements and terminal locations. See Fig. 50 for
typical CO
sensor wiring schematic.
2
To connect the sensor to the control, identify the positive
(4 to 20 mA) and ground (SIG COM) terminals on the
sensor. See Fig. 50. Connect the 4--20 mA terminal to
terminal TB1--9 and connect the SIG COM terminal to
terminal TB1--7. See Fig. 64.
IAQ Sensor
SEN
COM
J4-2
J4-3
24 VAC
C08462
Fig. 64 -- RTU--MP / Indoor CO2Sensor
(33ZCSENCO2) Connections
Outdoor Air Quality Sensor (PNO 33ZCSENCO2 plus
weatherproof enclosure) — The outdoor air CO
designed to monitor carbon dioxide (CO
sensor is
2
) levels in the
2
48TC
outside ventilation air and interface with the ventilation
damper in an HVAC system. The OAQ sensor is packaged
with an outdoor cover. See Fig. 52. The outdoor air CO
2
sensor must be located in the economizer outside air hood.
Wiring the Outdoor Air CO
Sensor — A dedicated power
2
supply is required for this sensor. A two--wire cable is
required to wire the dedicated power supply for the sensor.
)
2
The two wires should be connected to the power supply
and terminals 1 and 2.
To connect the sensor to the control, identify the positive
(4 to 20 mA) and ground (SIG COM) terminals on the
OAQ sensor. See Fig. 50. Connect the 4 to 20 mA
terminal to 48TC’s terminal TB1--11. Connect the SIG
COM terminal to 48TC’s terminal TB1--13. See Fig. 65.
OAQ Sensor/RH Sensor
SEN
J4-5
To accurately monitor the quality of the air in the
conditioned air space, locate the sensor near a return--air
grille (if present) so it senses the concentration of CO
leaving the space. The sensor should be mounted in a
location to avoid direct breath contact.
Do not mount the IAQ sensor in drafty areas such as near
supply ducts, open windows, fans, or over heat sources.
Allow at least 3 ft (0.9 m) between the sensor and any
corner. Avoid mounting the sensor where it is influenced
by the supply air; the sensor gives inaccurate readings if
the supply air is blown directly onto the sensor or if the
supply air does not have a chance to mix with the room air
before it is drawn into the return airstream.
Wiring the Indoor Air Quality Sensor —
For each sensor, use two 2--conductor 18 AWG (American
Wire Gage) twisted--pair cables (unshielded) to connect
the separate isolated 24 vac power source to the sensor
and to connect the sensor to the control board terminals.
COM
2
24 VAC
Fig. 65 -- RTU--MP / Outdoor CO2Sensor
(33ZCSENCO2) Connections
On 48TC units equipped with factory--installed Smoke
Detector(s), the smoke detector controller implements the
unit shutdown through its NC contact set connected to the
unit’s LCTB input. The FSD function is initiated via the
smoke detector’s Alarm NO contact set. The PremierLink
communicates the smoke detector’s tripped status to the
CCN building control. See Fig. 23 for unit smoke detector
wiring.
TheFireShutdownSwitchconfiguration,
→
MENU
Config→Inputs→input5,identifiesthe
normally open status of this input when there is no fire
alarm.
47
J4-6
C08463
Alarm state is reset when the smoke detector alarm
condition is cleared and reset at the smoke detector in the
unit.
Connecting Discrete Inputs
Filter Status
The filter status accessory is a field--installed accessory.
This accessory detects plugged filters. When installing
this accessory, the unit must be configured for filter status
by setting MENU
to Filter Status and normally open (N/O) or normally
closed (N/C). Input 8 or 9 is recommended for easy of
installation. Refer to Fig. 59 and Fig. 60 for wire
terminations at J5.
Status
Fan
The fan status accessory is a field--installed accessory.
This accessory detects when the indoor fan is blowing air.
When installing this accessory, the unit must be
48TC
configuredforfanstatusbysetting
→
MENU
Config→Inputs→input3,5,8,or9to Fan
Status and normally open (N/O) or normally closed (N/C).
Input 8 or 9 is recommended for easy of installation. Refer
to Fig. 59 and Fig. 60 for wire terminations at J5.
Remote
Occupancy
The remote occupancy accessory is a field--installed
accessory. This accessory overrides the unoccupied mode
and puts the unit in occupied mode. When installing this
accessory, the unit must be configured for remote
occupancy by setting MENU5, 8, or 9 to Remote Occupancy and normally open (N/O)
or normally closed (N/C).
Also set MENU
on/off. Input 8 or 9 is recommended for easy of
installation. Refer to Fig. 59 and Table 21 for wire
terminations at J5.
→
Config→Inputs→input3,5,8,or9
→
Config→Inputs→input 3,
→
Schedules→occupancy source to DI
Power Exhaust (output)
Connect the accessory Power Exhaust contactor coil(s) per
Fig. 66.
Power Exhaust
PEC
TAN
J11-3
LCTB
THERMOSTAT
GRA
Fig. 66 -- RTU--MP Power Exhaust Connections
Space Relative Humidity Sensor -- The RH sensor is not
used with 48TC models at this time.
C
C08464
Communication Wiring -- Protocols
General
Protocols are the communication languages spoken by
control devices. The main purpose of a protocol is to
communicate information in the most efficient method
possible. Different protocols exist to provide different
kinds of information for different applications. In the BAS
application, many different protocols are used, depending
on manufacturer. Protocols do not change the function of
a controller; just make the front end user different.
The RTU--MP can be set to communicate on four different
protocols: BACnet, Modbus, N2, and LonWorks. Switch 3
(SW3) on the board is used to set protocol and baud rate.
Switches 1 and 2 (SW1 and SW2) are used to set the
board’s network address. See Fig 67 for the switch setting
per protocol. The 3rd party connection to the RTU--MP is
through plug J19. Refer to the RTU--MP 3rd PartyIntegration Guide for more detailed information on
protocols, 3rd party wiring, and networking.
NOTE: Power must be cycled after changing the SW1--3
switch settings.
SW3 Protocol Selection
PROTOCOLDS8DS7DS6DS5DS4DS3DS2DS1
BACnet MS/TP
(Master)
Modbus
(Slave)
N2
(Slave)
LonWorksUnusedONONOFFONOFFOFFOFF
NOTE:
DS = Dip Switch
BACnet MS/TP SW3 example shown
BAUD RATEDS2DS1
9600OFFOFF
19,200ONOFF
38,400OFFON
76,800ONON
UnusedOFFOFFOFFONOFFSelect Baud Select Baud
UnusedOFFOFFONONOFFSelect BaudSelect Baud
UnusedOFFOFFOFFONONOFFOFF
Baud Rate Selections
Fig. 67 -- RTU--MP SW3 Dip Switch Settings
48
C07166
BACnet MS/TP
BACnet Master Slave/Token Passing (MS/TP) is used for
communicatingBACnetoverasub--networkof
BACnet--only controllers. This is the default Carrier
communications protocol. Each RTU--MP module acts as
an MS/TP Master. The speed of an MS/TP network can
range from 9600 to 76.8K baud. Physical Addresses can
be set from 01 to 99.
Modbus
The RTU--MP module can speak the Modicon Modbus
RTU Protocol as described in the Modicon Modbus
Protocol Reference Guide, PI--MBUS--300 Rev. J. The
speed of a Modbus network can range from 9600 to 76.8K
baud. Physical Addresses can be set from 01 to 99.
Johnson
N2
N2 is not a standard protocol, but one that was created by
Johnson Controls, Inc. that has been made open and
available to the public. The speed of N2 network is
limited to only 9600 baud. Physical Addresses can be set
from 01 to 99.
orks
LonW
LonWorks is an open protocol that requires the use of
Echelon’s Neuron microprocessor to encode and decode
the LonWorks packets. In order to reduce the cost of
adding that hardware on every module, a separate
LonWorks Option Card (LON--OC) was designed to
connect to the RTU--MP.
This accessory card is needed for LonWorks and has to be
ordered and connected using the ribbon cable to plug J15.
The RTU--MP’s baud rate must be set to 38.4k to
communicate with the LON--OC. The address switches
(SW1 & SW2) are not used with LonWorks.
Access
Local
BACview6Handheld
The BACview6is a keypad/display interface used to
connect to the RTU--MP to access the control information,
read sensor values, and test the RTU, see Fig. 68. This is
an accessory interface that does not come with the MP
controller and can only be used at the unit. Connect the
6
BACview
to the RTU--MP’s J12 local access port. There
are 2 password protected levels in the display (User and
Admin). The user password is defaulted to 0000 but can
be changed. The Admin password is 1111 and cannot be
changed. There is a 10 minute auto logout if a screen is
left idle. See Form 48--50H--T--2T, Appendix A for
navigation and screen content.
Virtual BACview
Virtual BACview is a freeware computer program that
6
functions as the BACview
Handheld. The USB Link
interface (USB--L) is required to connect a computer to
the RTU--MP board. The link cable connects a USB port
to the J12 local access port. This program functions and
operates identical to the handheld.
RTU--MP Troubleshooting
Communication LEDs
The LEDs indicate if the controller is speaking to the
devices on the network. The LEDs should reflect
communication traffic based on the baud rate set. The
higher the baud rate the more solid the LEDs will appear.
48TC
Fig. 68 -- BACview6Handheld Connections
49
C07170
48TC
Table 22 – LEDs
The LEDs on the RTU--MP show the status of certain functions
If this LED is on...Status is...
PowerThe RTU MP has power
RxThe RTU MP is receiving data from the network segment
TxThe RTU MP is transmitting data over the network segment
DO#The digital output is active
The Run and Error LEDs indicate control module and network status
If Run LED shows...
2 flashes per secondOffNormal
2 flashes per second
2 flashes per second
2 flashes per second
2 flashes per secondOn
5 flashes per secondOnExec start ---up aborted, Boot is running
5 flashes per secondOff
7 flashes per second
14 flashes per second
OnOn
And Error LED shows...Status is...
2flashes,
alternating with Run LED
3flashes,
then off
4flashes,
then pause
7 flashes per second, alternating with
Run LED
14 flashes per second,
alternating with Run LED
Five minute auto---restart delay after system error
Control module has just been
formatted
Two or more devices on this network
havethesameARC156networkaddress
Exec halted after frequent system errors
or control programs halted
Firmware transfer in progress, Boot is
running
Ten second recovery period after brownout
Brownout
Failure. Try the following solutions:
STurn the RTU --- MP off, then on.
SFo r m at t h e RTU --- M P.
SDownload memory to the RTU ---MP.
SReplace the RTU ---MP.
50
Table 23 – Tr oubleshooting Alarms
BACnet
POINT NAME
Safety Chain Alarmsafety_chain
Fire Shutdown Alarmfire_alarm
Space Temp Sensor
Failure
SAT Sensor Alarmsat_alarm
High Space Temp Alarmspt_hiAlarm GeneratedAutomatic
Low Space Temp Alarmspt_loAlarm GeneratedAutomatic
High Supply Air Tempsat_hiAlarm GeneratedAutomatic
Low Supply Air Tempsat_loAlarm GeneratedAutomatic
Supply Fan Failed to
Start
Supply Fan in Handsf_hand
Compressor Safety
Alarm
Setpoint Slider Alarmslide_alarm
Dirty Filter AlarmfilterAlarm Generated
Switch Configuration
Alarm
Misconfigured Analog Input
OAT Sensor Alarmoat_alarm
Space RH Sensor Alarmsprh_alarm
Outdoor RH Sensor
Alarm
High Space Humiditysprh_hiAlarm GeneratedAutomatic
Low Space Humiditysprh_loAlarm GeneratedAutomaticIRH is less then 35% for more then 10 minutes.
IAQ Sensor Alarmiaq_alarm
OAQ Sensor Alarmoaq_alarm
High Carbon Dioxide
Level
Supply Fan Runtime
Alarm
Compressor 1 Runtime
Alarm
Compressor 2 Runtime
Alarm
OBJECT
NAME
spt_alarm
sf_fail
dx_compstatAlarm GeneratedAutomaticCompressor would not start.
sw_cfg_alarm
an_cfg_alarm
oarh_alarmAlarm GeneratedAutomatic
co2_hiAlarm GeneratedAutomaticCO2 reading is above 1200ppm.
Alarm Generated
Disables IAQ
Operation Economizer moves to minimum position
Alarm Generated Set
OAQ to 400
RESET
METHOD
AutomaticOver load Indoor Fan or Electric Heater overheat.
Automatic
Automatic
Automatic
Automatic
AutomaticBad Fan Status Switch, Configuration incorrect.
Automatic
Automatic/
reset timer
when configured with or
without
switch
Configure
correctly
Configure
correctly
Automatic
Automatic
Automatic
Automatic
clear the
timer
clear the
timer
clear the
timer
Smoke detected by smoke detector or configuration incorrect
Faulty, shorted, or open thermistor caused by
wiring error or loose connection.
Faulty, shorted, or open thermistor caused by
wiring error or loose connection.
Thespacetemperaturehasrisenabovethecool
setpoint by more than the desired amount.
The space temperature has dropped below the
heat setpoint by more than the desired amount.
SAT is greater then 160 degrees for more than 5
minutes.
Thesupplyairtemperatureisbelow35_Ffor
more than 5 minutes.
Tripped Circuit Breaker, Broken belt, Bad indoor
fan motor, Configuration incorrect, Bad fan status
switch.
STOsensorisopenorshortedformorethen5
seconds.
Dirty Filter, supply fan run time exceeded, filter
switch configuration wrong.
More than one binary input is configured for the
same purpose. More then one discrete input is
configured to provide the same function.
More then one analog input is configured to providethesamefunction.
Faulty, shorted, or open thermistor caused by
wiring error or loose connection.
Sensor reading is out of range. Bad sensor, bad
wiring, or sensor configured incorrectly.
Sensor reading is out of range. Bad sensor, bad
wiring, or sensor configured incorrectly.
IRH is greater then 70% for more then 10 minutes.
Sensor reading is out of range. Bad sensor, bad
wiring, or sensor configured incorrectly.
Sensor reading is out of range. Bad sensor, bad
wiring, or sensor configured incorrectly.
Supply fan run time exceeded user defined limit.
Compressor run time limit is exceeded.
Compressor run time limit is exceeded.
PROBABLE CAUSE
48TC
51
Alarms
Alarms can be checked through the network and/or the
local access. All the alarms are listed in Table 23 with
name, object name, action taken by control, reset method,
and probable cause. There are help screens for each alarm
on the local access displayand listed in Form
48--50H--T--2T, Appendix A: Help Screens. Some alarms
are explained in detail below.
Safety Chain
This alarm occurs immediately if the supply--fan internal
overload trips or if an electric--heat limit switch trips. The
Unit Status will be Shutdown and the System Mode will
be Disable. When this happens LCTB (R terminal) will
not have 24 VAC, but the RTU--MP board will still be
powered. All unit operations stop immediately and will
not restart until the alarm automatically clears. There are
no configurations for this alarm; it is all based on internal
48TC
wiring. This alarm will never occur if Fire Shutdown
Alarm is active.
Fire Shutdown
This alarm occurs immediately when the smoke detector
senses smoke. The Unit Status will be Shutdown and the
System Mode will be Disable. All unit operations stop
immediately and will not restart until the alarm
automatically clears. If there is not a smoke detector
installed or the smoke detector did not trip, check input
configurations.
Space Temp Sensor Failur
This alarm occurs if the space sensor wired to the
RTU--MP is disconnected or shorted for more then 10
seconds. When this occurs the Unit Status will be
Shutdown and the System Mode will be Run. Sensor,
sensorconnections,wiring, boardconnection,and
configurations should be checked for faults or errors.
Alarm will reset automatically when cause is fixed.
SA T Sensor
This alarm occurs immediately when the supply air
temperature sensor wired to the RTU--MP is disconnected
or shorted. When this occurs the Unit Status will be
Shutdown and the System Mode will be Run. Sensor,
sensorconnections,wiring, boardconnection,and
configurations should be checked for faults or errors.
Alarm will reset automatically when cause is fixed.
Switch Configuration
This occurs if more than one binary input (inputs 3, 5, 8,
and 9) is configured for the same function. When this
happens the two inputs (or more) configured wrong will
be disabled as an inputs. This alarm will automatically be
cleared when configuration is corrected.
An example of this would be: Input 3 = Compressor
Safety, input 5 = Fan Status, input 8 = Fan Status, and
input 9 = Humidistat; the alarm would be active, unit
would run, compressor safety and humidistat would
function normally, and Fan Status (inputs 5 & 8) will be
interpreted as “No Function.”
Alarm
Alarm
e
Alarm
Alarm
Misconfigured Analog
Input
This occurs if more than one analog input (inputs 1 & 2)
is configured for the same sensor. When this happens the
two inputs will be disabled as inputs. This alarm will
automatically be cleared when configuration is corrected.
An example of this would be: Input 1 = IAQ Sensor, input
2 = IAQ Sensor; the alarm would be active, unit would
run, but the IAQ Sensor (inputs 1 & 2) will be interpreted
as “No Function.”
Third Party
Networking
Thirdpartycommunicationandnetworking
troubleshooting should be done by or with assistance from
the front end 3rd party technician. A Module Status
6
Report (Modstat) can be run from the BACview
,see
Table 24 to perform. This lists information about the
boardstatusandnetworkingstate.Forbasic
troubleshooting, see Table 25. Refer to the RTU--MP 3rdParty Integration Guide for additional information.
BACnet MS/TP
1. Verify that the BAS and controller are both set to
speak the BACnet MS/TP protocol. The protocol of
the controller is set via SW3 (switches 3, 4, 5, and 6).
The protocol can also be verified by getting a Modstat
of the controller through the BACview. Hit the “FN”
key and the ’.’ key at the same time to pull up a
Modstat. Scroll to the bottom of the page and there is
a section entitled “Network Communications.” The
active protocol and baud rate will be shown in this
section.
2. Verify that the BAS and controller are set for the
same baud rate. The baud rate of the controller is set
via SW3 (switches 1 and 2). The baud rate can also
be verified via the BACview by obtaining a Modstat.
(See Fig. 67.)
3. Verify that the BAS is configured to speak 2--wire
EIA--485 to the controller. The BAS may have to configure jumper or DIP switches on their end.
4. Verify that the BAS and the controller have the same
communication settings (8 data bits, No Parity, and 1
stop bit).
5. Verify that the controller has a unique MAC address
on the MS/TP bus. The controller’s MS/TP MAC address is set by its rotary address switches.
6. Verify proper wiring between the BAS and the controller.
7. Verify that the BAS is reading or writing to the proper
BACnet objects in the controller. Download the latest
points list for the controller to verify.
8. Verify that the BAS is sending his requests to the
proper MS/TP MAC address of our controller.
9. Present the BAS company with a copy of our controller’s BACnet PICS so that they know which BACnet
commands are supported. See below.
10. In certain situations, it may be necessary to tweak the
MS/TP Protocol timing settings through the BAC-
6
. There are two settings that may be tweaked:
view
52
S Max Masters: Defines the highest MS/TP Master MAC
address on this MS/TP network. For example, if there are
3 master nodes on an MS/TP network, and their MAC
addresses are 1, 8, and 16, then Max Masters would be set
to 16 (since this is the highest MS/TP MAC address on
the network). This property optimizes MS/TP network
communications by preventing token passes and “poll for
Device Instance: 0160001
1 PRGs loaded. 1 PRGs running.
Module status:
Firmware sections validated in flash memory
============================================
Boot16-H - v2.06:001 Jun 19 2007
RTU-MP DRIVER - v2.09:050 Jun 26 2007
master” requests to non--existent Master nodes (i.e., in
the above example, MAC address 16 would know to pass
the token back to MAC address 1 instead of counting up
to MAC address 127). Each MS/TP master node on the
network must have their Max Masters set to this same
value. The default is 127.
48TC
System error message history: Type Specific
Warning message history:
Information message history:
POWERUP: BACnet reinitialize warmstart 06/29/07 10:49:40
Menu file not found. 06/29/07 10:48:35
ARC156 reconfigurations during the last hour (cleared upon reset):
Total ....................... 0
Initiated by this node ...... 0
Core board hardware:
Type=147, board=34, manufactured on 05/14/2007, S/N 21A740188N
RAM: 1024 kBytes; FLASH: 1024 kBytes, type = 3
Base board hardware:
Type=147, board=71, manufactured on 05/14/2007, S/N RMP750037N
When troubleshooting, you may need to know a control module’s manufacture date
Obtain the manufacture date from
a...
Module status report (modstat)To obtain a modstat with BACview6:
Sticker on the back of the main control
module board
”Serial No: RMPYMxxxxN”
(Bar Coded & Typed Number)
Notes
1. Press Function (FN) key and hold.
2. Then press period (.)
3. Release both buttons.
ThereportshowsthedateunderMain board hardware.
The serial numbers are unique and contain embedded information:
“RMP”---These first three digits are unique to RTU---MP and are used as an identifier .
“YM”---These two digits identify the last digit of the year and month (in hex, A=10/Oct)
of manufacture. ”74” would represent a date of manufacture of ”April 2007”.
“xxxx”---These four digits represent the sequential number of units produced for a given
product for the mentioned manufacturing time period.
“N”---This final digit represents the decade and toggles between ”N” and ”M” every
ten years.
Table 25 – Basic Protocol Troubleshooting
48TC
ProblemPossible causeCorrective action
No communication with 3rd
party vendor
Incorrect settings on SW1, SW2 and SW3Verify and correct switch settings. Cycle
RS485 Port has no voltage outputVerify RTU---MP has correct power supply
(check with RTU---MP disconnected from RS485 communication bus)
Bacnet @ 9600/19.2K --- .01 to .045vdcCheck RS485 bus for external before re-
Bacnet @ 38.4K --- .06 to .09vdcVolt age, shorts or grounding
Bacnet @ 76.8K --- .1vdcbefore reconnecting to the bus
Modbus @ 9600 --- 76.8K --- .124vdc
N2 @ 9600 --- .124vdc
Verify devices are daisy chained and repeaters and bias
terminators are correctly installed
powertoRTU---MPafterchangingswitch
settings.
Possible bad driver on board.
connecting to the bus
Check 3rd party vendor RS485 communication wiring guidelines and troubleshooting procedures
S MaxInfo Frames: This property defines the maximum
number of responses that will be sent when our controller
gets the token. A valid number is any positive integer.
The default is 10 and should be ideal for the majority of
applications. In cases where the controller is the target of
many requests, this number could be increased as high as
100 or 200.
NOTE:MS/TP networks can be comprised of both
Master and Slave nodes. Valid MAC addresses for Master
nodes are 0 -- 127 and valid addresses for Slave nodes are
0 -- 254.
NOTE:See RTU--MP 3rd Party Integration Guide (or
alternatively Form 48--50H--T--1T Appendix) for Protocol
Maps.
Table 26 – Modbus Exception Codes that May be
Returned From This Controller
CODENAMEMEANING
The Modbus function code used
01Illegal Function
02Illegal Data Address
04SlaveDeviceFailure
in the query is not supported by
the controller .
The register address used in the
query is not supported by the
controller.
The Modbus Master has attempted to write to a non---existent register or a read--- only register in the controller.
Modbus
1. Verify that the BAS and controller are both set to
speak the Modbus RTU protocol. The protocol of the
controller is set via SW3 (switches 3, 4, 5, and 6).
The protocol can also be verified by getting a Modstat
of the controller through the BACview. Hit the ”FN”
key and the ’.’ key at the same time to pull up a
Modstat. Scroll to the bottom of the page and there is
a section entitled “Network Communications.” The
active protocol and baud rate will be shown in this
section.
2. Verify that the BAS and controller are set for the
same baud rate. The baud rate of the controller is set
via SW3 (switches 1 and 2). The baud rate can also
be verified via the BACview by obtaining a Modstat
(see above).
3. Verify that the BAS is configured to speak 2--wire
EIA--485 to the controller. The BAS may have to configure jumper or DIP switches on their end.
4. Verify that the BAS and the controller have the same
communication settings (8 data bits, No Parity, and 1
stop bit).
5. Verify that the controller has a unique Modbus slave
address. The controller’s Modbus slave address is set
by its rotary address switches.
6. Verify that the BAS is using the proper Modbus function codes to access data from our controller. Supported function codes are shown above.
54
7. Verify proper wiring between the BAS and the con-
A
troller.
8. Verify that the BAS is reading or writing to the proper
Modbus register numbers on the controller. Download
the latest points list for the controller to verify.
9. Verify that the BAS is sending his requests to the
proper slave address of our controller.
NOTE:See RTU--MP 3rd Party Integration Guide (or
alternatively Form 48--50H--T--1T, Appendix) for Modbus
Protocol Conformance Statement.
N2
1. Verify that the BAS and controller are both set to
speak the N2 protocol. The protocol of the controller
is set via SW3 (switches 3, 4, 5, and 6). The protocol
can also be verified by getting a Modstat of the controller through the BACview. Hit the “FN” key and
the ’.’ key at the same time to pull up a Modstat.
Scroll to the bottom of the page and there is a section
entitled ”Network Communications.” The active protocol and baud rate will be shown in this section.
2. Verify that the BAS and controller are set for 9600
baud. The baud rate of the controller is set via SW3
(switches 1 and 2). The baud rate can also be verified
via the BACview by obtaining a Modstat (see above).
3. Verify that the BAS is configured to speak 2--wire
EIA--485 to the controller. The BAS may have to configure jumper or DIP switches on their end.
4. Verify that the BAS and the controller have the same
communication settings (8 data bits, No Parity, and 1
stop bit).
5. Verify that the controller has a unique N2 slave address on the N2 bus. The controller’s N2 slave address is set by its rotary address switches.
6. Verify proper wiring between the BAS and the controller.
7. Verify that the BAS is reading or writing to the proper
network point addresses on the controller. Download
the latest points list for the controller to verify.
8. Verify that the BAS is sending his requests to the
proper slave address of our controller.
NOTE:See RTU--MP 3rd Party Integration Guide (or
alternatively Form 48--50H--T--1T Appendix) for N2
Protocol Conformance Statement.
ECONOMIZER SYSTEMS
The 48TC units may be equipped with a factory--installed
or accessory (field--installed) economizer system. Two
types areavailable:with a logic controlsystem
(EconoMi$erIV)andwithoutacontrolsystem
(EconoMi$er2, for use with external control systems such
as PremierLink). See Fig. 70 and Fig. 71 for component
locations on each type. See Fig. 72 and Fig. 73 for
economizer section wiring diagrams.
Both EconoMi$ers use direct--drive damper actuators.
ECONOMI$ER IV
CONTROLLER
WIRING
HARNESS
CTUATOR
Fig. 70 -- EconoMi$er IV Component Locations
ECONOMI$ER2
PLUG
BAROMETRIC
RELIEF
DAMPER
Fig. 71 -- EconoMi$er2 Component Locations
OUTSIDE AIR
TEMPERATURE SENSOR
LOW AMBIENT
SENSOR
OUTDOOR
AIR HOOD
HOOD
SHIPPING
BRACKET
GEAR DRIVEN
DAMPER
C06021
C06022
48TC
55
48TC
DCV— Demand Controlled Ventilation
IAQ — Indoor Air Quality
LA — Low Ambient Lockout Device
OAT — Outdoor-Air Temperature
POT— Potentiometer
RAT— Return-Air Temperature
FOR OCCUPANCY CONTROL
REPLACE JUMPER WITH
FIELD-SUPPLIED TIME CLOCK
NOTES:
1. 620 ohm, 1 watt 5% resistor should be removed only when using differential
enthalpy or dry bulb.
2. If a separate field-supplied 24 v transformer is used for the IAQ sensor power
supply, it cannot have the secondary of the transformer grounded.
3. For field-installed remote minimum position POT, remove black wire jumper
between P and P1 and set c ontrol minimum position POT to the minimum
position.
C06028
BLACK
4
TRANSFORMER
GROUND
3
5
BLUE
500 OHM
RESISTOR
VIOLET
NOTE 1
RUN
NOTE 3
50HJ540573
ACTUATOR
ASSEMBLY
DIRECT DRIVE
ACTUATOR
NOTES:
1. Switch on actuator must be in run position for economizer to operate.
2. PremierLink™ control requires that the standard 50HJ540569 outside-air sensor be replaced by either the CROASENR001A00 dry bulb sen
sor or HH57A077 enthalpy sensor.
3. 50HJ540573 actuator consists of the 50HJ540567 actuator and a harness with 500-ohm resistor.
OAT SENSOR
4-20mA SIGNAL
PINK
YELLOW
WHITE
2
8
6
7
RED
24 VAC
1
10
11
9
12
ECONOMISER2 PLUG
4-20 mA
TO J9 ON
PremierLink
BOARD
C08310
Fig. 73 -- EconoMi$er2 with 4 to 20 mA Control Wiring
56
Table 27 – EconoMi$er IV Input/Output Logic
INPUTSOUTPUTS
Demand Control
Ventilation (DCV)
(Free Cooling LED
Below set
(DCV LED Off)
(Free Cooling LED
(Free Cooling LED
Above set
(DCV LED On)
(Free Cooling LED
*For single enthalpy control, the module compares outdoor enthalpy to the ABCD setpoint.
†Power at N terminal determines Occupied/Unoccupied setting: 24 vac (Occupied), no power (Unoccupied).
** Modulation is based on the supply-air sensor signal.
†† Modulation is based on the DCV signal.
*** Modulation is based on the greater of DCV and supply-air sensor signals, between minimum position and either maximum position (DCV)
or fully open (supply-air signal).
††† Modulation is based on the greater of DCV and supply-air sensor signals, between closed and either maximum position (DCV) or fully
open (supply-air signal).
Enthalpy*
OutdoorReturn
High
Low
Off)
Low
High
On)
High
Low
Off)
Low
High
On)
Y1Y2
On OnOnOn
OffOffOffOff
On OnOnOff
OnOffOffOff
OffOffOffOffMinimum positionClosed
On OnOnOn
OnOffOnOff
OffOffOffOff
On OnOnOff
OffOffOffOff
CompressorNTerminal†
Stage1Stage
2
OccupiedUnoccupied
Damper
Minimum positionClosedOnOffOnOff
Modulating** (between
min. position and full-
open)
Modulating†† (between
min. position and DCV
maximum)
Modulating***Modulating†††OnOffOffOff
Modulating** (be-
tween closed and
full-open)
Modulating†† (be-
tween closed and
DCV
maximum)
48TC
Fig. 74 -- EconoMi$er IV Functional View
EconoMi$er IV
Table 27 provides a summary of EconoMi$er IV.
Troubleshooting instructions are enclosed.
A functional view of the EconoMi$er is shown in Fig. 74.
Typical settings, sensor ranges, and jumper positions are
also shown. An EconoMi$er IV simulator program is
available from Carrier to help with EconoMi$er IV
training and troubleshooting.
C06053
EconoMi$er IV Standard
Sensors
Outdoor Air Temperature (OAT) Sensor
The outdoor air temperature sensor (HH57AC074) is a 10
to 20 mA device used to measure the outdoor-air
temperature. The outdoor-air temperature is used to
determine when the EconoMi$er IV can be used for free
cooling.Thesensorisfactory-installedonthe
EconoMi$er IV in the outdoor airstream. (See Fig. 75.)
The operating range of temperature measurement is 40_ to
100_F(4_ to 38_C). See Fig. 77.
57
Supply Air Temperature (SAT) Sensor
The supply air temperature sensor is a 3 K thermistor
located at the inlet of the indoor fan. (See Fig. 75.) This
sensor is factory installed. The operating range of
temperature measurement is 0° to 158_F(--18_ to 70_C).
See Table 15 for sensor temperature/resistance values.
SUPPLY AIR
TEMPERATURE
SENSOR
MOUNTING
LOCATION
SUPPLY AIR
TEMPERATURE
SENSOR
and D. See Fig. 77 for the corresponding temperature
changeover values.
48TC
Fig. 75 -- Supply Air Sensor Location
The temperature sensor looks like an eyelet terminal with
wires running to it. The sensor is located in the “crimp
end” and is sealed from moisture.
Outdoor Air Lockout Sensor
The EconoMi$er IV is equipped with an ambient
temperature lockout switch located in the outdoor
airstream which is used to lock out the compressors below
a42_F(6_C) ambient temperature. (See Fig. 70.)
EconoMi$er IV Control
Modes
IMPORTANT: The optional EconoMi$er2 does not
include a controller. The EconoMi$er2 is operated by a 4
to 20 mA signal from an existing field-supplied controller
(such as PremierLink™ control). See Fig. 72 for wiring
information.
Determine the EconoMi$er IV control mode before set up
of the control. Some modes of operation may require
different sensors. (See Table 22.) The EconoMi$er IV is
supplied from the factory with a supply--air temperature
sensor and an outdoor-- air temperature sensor. This allows
for operation of the EconoMi$er IV with outdoor air dry
bulb changeover control. Additional accessories can be
added to allow for different types of changeover control
and operation of the EconoMi$er IV and unit.
Outdoor Dry Bulb Changeover
The standard controller is shipped from the factory
configured for outdoor dry bulb changeover control. The
outdoor air and supply air temperature sensors are
included as standard. For this control mode, the outdoor
temperature is compared to an adjustable setpoint selected
on the control. If the outdoor-air temperature is above the
setpoint, the EconoMi$er IV will adjust the outside air
dampersto minimumposition.If theoutdoor-air
temperature is below the setpoint, the position of the
outside air dampers will be controlled to provided free
cooling using outdoor air. When in this mode, the LED
next to the free cooling setpoint potentiometer will be on.
The changeover temperature setpoint is controlled by the
free cooling setpoint potentiometer located on the control.
(See Fig. 76.) The scale on the potentiometer is A, B, C,
C06033
C06034
Fig. 76 -- EconoMi$er IV Controller Potentiome t er
and LED Locations
19
LED ON
mA
18
17
16
15
14
13
12
11
10
9
40
LED OFF
45
D
50
60
55
DEGREES FAHRENHEIT
LED ON
LED OFF
65
C
LED ON
B
LED ON
A
LED OFF
100
90
85
80
95
C06035
70
LED OFF
75
Fig. 77 -- Outside Air Temperature Changeover
Setpoints
30
25
20
15
10
5
0
0.13 0.20 0.22 0. 25 0.30 0. 35 0.40 0.45 0.50
FLOW IN CUBIC FEET PER MINUTE (cfm)
STATIC PRESSURE (in. wg)
C06031
Fig. 78 -- Outdoor--Air Damper Leakage
Differential Dry Bulb Control
For differential dry bulb control the standard outdoor dry
bulb sensor is used in conjunction with an additional
accessorydrybulbsensor(partnumber
CRTEMPSN002A00). The accessory sensor must be
mounted in the return airstream. (See Fig. 79.) Wiring is
58
provided in the EconoMi$er IV wiring harness. (See Fig.
70.)
ECONOMI$ERIV
CONTROLLER
ECONOMI$ERIV
GROMMET
RETURN AIR
SENSOR
RETURN DUCT
(FIELD-PROVIDED)
C07085
Fig. 79 -- Return Air Temperature or Enthalpy Sensor
Mounting Location
In this mode of operation, the outdoor-air temperature is
compared to the return-air temperature and the lower
temperature airstream is used for cooling. When using this
mode of changeover control, turn the enthalpy setpoint
potentiometer fully clockwise to the D setting. (See Fig.
76.)
Outdoor Enthalpy Changeover
For enthalpy control, accessory enthalpy sensor (part
number HH57AC078) is required. Replace the standard
outdoor dry bulb temperature sensor with the accessory
enthalpy sensor in the same mounting location. (See Fig.
79.) When the outdoor air enthalpy rises above the
outdoor enthalpy changeover setpoint, the outdoor-air
damper moves to its minimum position. The outdoor
enthalpy changeover setpoint is set with the outdoor
enthalpy setpoint potentiometer on the EconoMi$er IV
controller. The setpoints are A, B, C, and D. (See Fig. 80.)
The factory-installed 620-ohm jumper must be in place
across terminals S
and SR+ on the EconoMi$er IV
R
controller.
48TC
CONTROL
CURVE
4
1
2
1
A
B
C
D
6
1
46
8
3
A
(18)
4
4
80
42
(21)
1
(27)
75
(24)
70
0
0
0
9
80
70
0
6
50
A
B
C
D
70
75
80
(24)
(21)
(27)
40
65
65
(18)
CONTROL POINT
deg. F (deg. C)
APPROX.
AT 50% RH
73 (23)
70 (21)
67 (19)
63 (17)
28
ENTHALPY BTU PER POUND DRY AIR
26
4
2
2
2
0
2
8
1
45
(7)
40
(4)
35
(2)
35
40
45
(2)
(4)
(7)
APPROXIMATE DRY BULB TEMPERATURE--degrees F (degrees C)
6
3
4
3
32
30
60
(16)
55
(13)
B
50
C
(10)
D
50
55
60
(10)
(13)
(16)
Fig. 80 -- Enthalpy Changeover Setpoints
85
(29)90(32)95(35)
RELATIVE HUMIDITY (%)
0
4
30
85
(29)90(32)95(35)
100
105
110
(38)
(41)
(43)
20
0
1
HIGH LIMIT
110
(43)
CURVE
(38)
105
100
(41)
C06037
59
N1
P1
T1
AQ1
SO+
SR+
CO SENSOR MAX RANGE SETTING
TR1
EXH
2V10V
EXH
Open
2V10V
DCV
2V10V
Free
Cool
B
A
Set
Min
Pos
DCV
Max
DCV
Set
C
D
N
P
T
AQ
SO
SR
TR
24
24 Vac
Va c
COM
HOT
_
+
12
5
4
3
EF1
EF
6000
5000
4000
3000
2000
1000
RANGE CONFIGURATION (ppm)
0
Fig. 82 -- CO2Sensor Maximum Range Settings
2
800 ppm
900 ppm
1000 ppm
1100 ppm
2345678
DAMPER VOLTAGE FOR MAX VENTILATION RATE
C06039
48TC
Fig. 81 -- EconoMi$er IV Control
Differential Enthalpy Control
For differential enthalpy control, the EconoMi$er IV
controller uses two enthalpy sensors (HH57AC078 and
CRENTDIF004A00), one in the outside air and one in the
return air duct. The EconoMi$er IV controller compares
the outdoor air enthalpy to the return air enthalpy to
determine EconoMi$er IV use. The controller selects the
lower enthalpy air (return or outdoor) for cooling. For
example, when the outdoor air has a lower enthalpy than
the return air, the EconoMi$er IV opens to bring in
outdoor air for free cooling.
Replace the standard outside air dry bulb temperature
sensor with the accessory enthalpy sensor in the same
mounting location. (See Fig. 70.) Mount the return air
enthalpy sensor in the return air duct. (See Fig. 79.)
Wiring is provided in the EconoMi$er IV wiring harness.
(See Fig. 70.) The outdoor enthalpy changeover setpoint is
set with the outdoor enthalpy setpoint potentiometer on
the EconoMi$er IV controller. When using this mode of
changeovercontrol,turntheenthalpysetpoint
potentiometer fully clockwise to the D setting.
Indoor Air Quality (IAQ) Sensor Input
The IAQ input can be used for demand control ventilation
control based on the level of CO
measured in the space
2
or return air duct.
MounttheaccessoryIAQsensoraccordingto
manufacturer specifications. The IAQ sensor should be
wired to the AQ and AQ1 terminals of the controller.
Adjust the DCV potentiometers to correspond to the DCV
voltage output of the indoor air quality sensor at the
user-determined setpoint. (See Fig. 82.)
C06038
If a separate field-supplied transformer is used to power
the IAQ sensor, the sensor must not be grounded or the
EconoMi$er IV control board will be damaged.
When using demand ventilation, the minimum damper
position represents the minimum ventilation position for
VOC(volatileorganiccompounds)ventilation
requirements. The maximum demand ventilation position
is used for fully occupied ventilation.
When demand ventilation control is not being used, the
minimum position potentiometer should be used to set the
occupied ventilation position. The maximum demand
ventilation position should be turned fully clockwise.
Exhaust Setpoint Adjustment
The exhaust setpoint will determine when the exhaust fan
runs based on damper position (if accessory power
exhaust is installed). The setpoint is modified with the
Exhaust Fan Setpoint (EXH SET) potentiometer. (See Fig.
76.) The setpoint represents the damper position above
which the exhaust fans will be turned on. When there is a
call for exhaust, the EconoMi$er IV controller provides a
45 ± 15 second delay before exhaust fan activation to
allow the dampers to open. This delay allows the damper
to reach the appropriate position to avoid unnecessary fan
overload.
Minimum Position Control
There is a minimum damper position potentiometer on the
EconoMi$er IV controller. (See Fig. 76.) The minimum
damper position maintains the minimum airflow into the
building during the occupied period.
When using demand ventilation, the minimum damper
position represents the minimum ventilation position for
VOC(volatileorganiccompound)ventilation
requirements. The maximum demand ventilation position
is used for fully occupied ventilation.
When demand ventilation control is not being used, the
minimum position potentiometer should be used to set the
occupied ventilation position. The maximum demand
ventilation position should be turned fully clockwise.
Adjust the minimum position potentiometer to allow the
minimum amount of outdoor air, as required by local
codes, to enter the building. Make minimum position
adjustments with at least 10_F temperature difference
between the outdoor and return-air temperatures.
60
To determine the minimum position setting, perform the
following procedure:
1. Calculate the appropriate mixed air temperature
using the following formula:
OA
(T
Ox
100100
+(TR
)
RA
x
)=T
M
TO= Outdoor-Air Temperature
OA = Percent of Outdoor Air
T
= Return-Air Temperature
R
RA = Percent of Return Air
= Mixed-Air Temperature
T
M
As an example, if local codes require 10% outdoor
airduringoccupiedconditions,outdoor-air
temperature is 60_F, and return-air temperature is
75_F.
(60 x .10) + (75 x .90) = 73.5_ F
2. Disconnect the supply air sensor from terminals T
and T1.
3. Ensure that the factory-installed jumper is in place
across terminals P and P1. If remote damper
positioning is being used, make sure that the
terminals are wired according to Fig. 59 and that the
minimum position potentiometer is turned fully
clockwise.
4. Connect 24 vac across terminals TR and TR1.
5. Carefullyadjusttheminimumposition
potentiometeruntilthemeasured mixedair
temperature matches the calculated value.
6. Reconnect the supply air sensor to terminals T and
T1.
Remote control of the EconoMi$er IV damper is desirable
when requiring additional temporary ventilation. If a
field-supplied remote potentiometer (Honeywell part
number S963B1128) is wired to the EconoMi$er IV
controller, the minimum position of the damper can be
controlled from a remote location.
To control the minimum damper position remotely,
remove the factory-installed jumper on the P and P1
terminals on the EconoMi$er IV controller. Wire the
field-supplied potentiometer to the P and P1 terminals on
the EconoMi$er IV controller. (See Fig. 81.)
Damper Movement
Damper movement from full open to full closed (or vice
1
versa) takes 2
/2minutes.
Thermostats
The EconoMi$er IV control works with conventional
thermostats that have a Y1 (cool stage 1), Y2 (cool stage
2), W1 (heat stage 1), W2 (heat stage 2), and G (fan). The
EconoMi$erIVcontroldoesnotsupportspace
temperature sensors. Connections are made at the
thermostat terminal connection board located in the main
control box.
Occupancy Control
The factory default configuration for the EconoMi$er IV
control is occupied mode. Occupied status is provided by
the black jumper from terminal TR to terminal N. When
unoccupied mode is desired, install a field--supplied
timeclock function in place of the jumper between TR and
N. When the timeclockcontacts areclosed, the
EconoMi$er IV control will be in occupied mode. When
the timeclock contacts are open (removing the 24--v signal
from terminal N), the EconoMi$er IV will be in
unoccupied mode.
Demand Control Ventilation (DCV)
When using the EconoMi$er IV for demand controlled
ventilation, there are some equipment selection criteria
which should be considered. When selecting the heat
capacity and cool capacity of the equipment, the
maximum ventilation rate must be evaluated for design
conditions. The maximum damper position must be
calculated to provide the desired fresh air.
Typically the maximum ventilation rate will be about 5 to
10% more than the typical cfm required per person, using
normal outside air design criteria.
A proportional anticipatory strategy should be taken with
the following conditions: a zone with a large area, varied
occupancy, and equipment that cannot exceed the required
ventilation rate at design conditions. Exceeding the
required ventilation rate means the equipment can
condition air at a maximum ventilation rate that is greater
thantherequiredventilationrateformaximum
occupancy. A proportional-anticipatory strategy will cause
the fresh air supplied to increase as the room CO
increases even though the CO
reached. By the time the CO
setpoint has not been
2
level reaches the setpoint,
2
2
level
the damper will be at maximum ventilation and should
maintain the setpoint.
In order to have the CO
sensor control the economizer
2
damper in this manner, first determine the damper voltage
output for minimum or base ventilation. Base ventilation
is the ventilation required to remove contaminants during
unoccupied periods. The following equation may be used
to determine the percent of outside air entering the
building for a given damper position. For best results there
should be at least a 10 degree difference in outside and
return-air temperatures.
OA
(T
Ox
100100
+(TR
)
RA
x
)=T
M
TO= Outdoor-Air Temperature
OA = Percent of Outdoor Air
T
= Return-Air Temperature
R
RA = Percent of Return Air
T
= Mixed-Air Temperature
M
Once base ventilation has been determined, set the
minimum damper position potentiometer to the correct
position.
The same equation can be used to determine the occupied
or maximum ventilation rate to the building. For example,
an output of 3.6 volts to the actuator provides a base
ventilation rate of 5% and an output of 6.7 volts provides
the maximum ventilation rate of 20% (or base plus 15 cfm
per person). Use Fig. 82 to determine the maximum
setting of the CO
sensor. For example, an 1100 ppm
2
setpoint relates to a 15 cfm per person design. Use the
1100 ppm curve on Fig. 82 to find the point when the CO
sensor output will be 6.7 volts. Line up the point on the
48TC
2
61
graph with the left side of the chart to determine that the
range configuration for the CO
sensor should be 1800
2
ppm. The EconoMi$er IV controller will output the 6.7
volts from the CO
sensor to the actuator when the CO
2
concentration in the space is at 1100 ppm. The DCV
setpoint may be left at 2 volts since the CO
voltage will be ignored by the EconoMi$er IV controller
until it rises above the 3.6 volt setting of the minimum
position potentiometer.
Once the fully occupied damper position has been
determined, set the maximum damper demand control
ventilation potentiometer to this position. Do not set to the
maximum position as this can result in over-ventilation to
the space and potential high humidity levels.
Sensor Configuration
CO
2
The CO2sensor has preset standard voltage settings that
can be selected anytime after the sensor is powered up.
(See Table 28.)
48TC
Use setting 1 or 2 for Carrier equipment. (See Table 28.)
1. Press Clear and Mode buttons. Hold at least 5
seconds until the sensor enters the Edit mode.
2. Press Mode twice. The STDSET Menu will appear.
Table 28 – EconoMi$er IV Sensor Usage
ECONOMI$ER IV WITH OUTDOOR AIR DRY
APPLICATION
Outdoor Air
Dry Bulb
Differential
Dry Bulb
Single EnthalpyHH57AC078
Differential
Enthalpy
CO2for DCV
Control using a
Wall-Mounted
CO
Sensor
2
CO2for DCV
Control using a
Duct-Mounted
CO
Sensor
2
* CRENTDIF004A00 and CRTEMPSN002A00 accessories are
used on many different base units. As such, these kits may
contain parts that will not be needed for installation.
† 33ZCSENCO2 is an accessory CO
** 33ZCASPCO2 is an accessory aspirator box required f or duct-
mounted applications.
†† CRCBDI OX005A00 is an accessory that contains both
33ZCSENCO2 and 33ZCASPCO2 accessories.
None. The outdoor air dry bulb sensor is
HH57AC078 and CRENTDIF004A00*
33ZCSENCO2† and
33ZCASPCO2**OR
BULB SENSOR
Accessories Required
factory installed.
CRTEMPSN002A00*
33ZCSENCO2
CRCBDIOX005A00††
sensor.
2
3. Use the Up/Down button to select the preset
number. (See Table 28.)
4. Press Enter to lock in the selection.
5. Press Mode to exit and resume normal operation.
The custom settings of the CO
sensor can be changed
2
anytime after the sensor is energized. Follow the steps
below to change the non-standard settings:
1. Press Clear and Mode buttons. Hold at least 5
seconds until the sensor enters the Edit mode.
2. Press Mode twice. The STDSET Menu will appear.
3. Use the Up/Down button to toggle to the NONSTD
menu and press Enter.
2
sensor
4. Use the Up/Down button to toggle through each of
the nine variables, starting with Altitude, until the
desired setting is reached.
2
5. Press Mode to move through the variables.
6. Press Enter to lock in the selection, then press Mode
to continue to the next variable.
Dehumidification of Fresh Air with DCV (Demand
Controlled Ventilation) Control
If normal rooftop heating and cooling operation is not
adequate for the outdoor humidity level, an energy
recovery unit and/or a dehumidification option should be
considered.
EconoMi$er IV Pr
eparation
This procedure is used to prepare the EconoMi$er IV for
troubleshooting. No troubleshooting or testing is done by
performing the following procedure.
NOTE:This procedure requires a 9--v battery, 1.2
kilo--ohm resistor, and a 5.6 kilo--ohm resistor which are
not supplied with the EconoMi$er IV.
IMPORTANT: Be sure to record the positions of all
potentiometers before starting troubleshooting.
1. Disconnect power at TR and TR1. All LEDs should
be off. Exhaust fan contacts should be open.
2. Disconnect device at P and P1.
3. Jumper P to P1.
4. Disconnect wires at T and T1. Place 5.6 kilo--ohm
resistor across T and T1.
5. Jumper TR to 1.
6. Jumper TR to N.
7. If connected, remove sensor from terminals SO and +.
Connect 1.2 kilo--ohm 4074EJM checkout resistor
across terminals SO and +.
8. Put 620--ohm resistor across terminals SR and +.
9. Set minimum position, DCV setpoint, and exhaust potentiometers fully CCW (counterclockwise).
10. Set DCV maximum position potentiometer fully CW
(clockwise).
11. Set enthalpy potentiometer to D.
12. Apply power (24 vac) to terminals TR and TR1.
Differential
Enthalpy
To check differential enthalpy:
1. Make sure EconoMi$er IV preparation procedure has
been performed.
2. Place 620--ohm resistor across SO and +.
3. Place 1.2 kilo--ohm resistor across SR and +. The
Free Cool LED should be lit.
4. Remove 620--ohm resistor across SO and +. The Free
Cool LED should turn off.
5. Return EconoMi$er IV settings and wiring to normal
after completing troubleshooting.
62
Single Enthalpy
To check single enthalpy:
1. Make sure EconoMi$er IV preparation procedure has
been performed.
2. Set the enthalpy potentiometer to A (fully CCW). The
Free Cool LED should be lit.
3. Set the enthalpy potentiometer to D (fully CW). The
Free Cool LED should turn off.
4. Return EconoMi$er IV settings and wiring to normal
after completing troubleshooting.
DCV (Demand Controlled Ventilation) and
Exhaust
To check DCV and Power Exhaust:
1. Make sure EconoMi$er IV preparation procedure has
been performed.
2. Ensure terminals AQ and AQ1 are open. The LED for
both DCV and Exhaust should be off. The actuator
should be fully closed.
3. Connect a 9--v battery to AQ (positive node) and AQ1
(negative node). The LED for both DCV and Exhaust
should turn on. The actuator should drive to between
90 and 95% open.
4. Turn the Exhaust potentiometer CW until the Exhaust
LED turns off. The LED should turn off when the potentiometer is approximately 90%. The actuator
should remain in position.
5. Turn the DCV setpoint potentiometer CW until the
DCV LED turns off. The DCV LED should turn off
when the potentiometer is approximately 9--v. The actuator should drive fully closed.
6. Turn the DCV and Exhaust potentiometers CCW until
the Exhaust LED turns on. The exhaust contacts will
close 30 to 120 seconds after the Exhaust LED turns
on.
7. Return EconoMi$er IV settings and wiring to normal
after completing troubleshooting.
DCV Minimum and Maximum
To check the DCV minimum and maximum position:
1. Make sure EconoMi$er IV preparation procedure has
been performed.
2. Connect a 9--v battery to AQ (positive node) and AQ1
(negative node). The DCV LED should turn on. The
actuator should drive to between 90 and 95% open.
3. Turn the DCV Maximum Position potentiometer to
midpoint. The actuator should drive to between 20
and 80% open.
4. Turn the DCV Maximum Position potentiometer to
fully CCW. The actuator should drive fully closed.
Position
Power
5. Turn the Minimum Position potentiometer to midpoint. The actuator should drive to between 20 and
80% open.
6. Turn the Minimum Position Potentiometer fully CW.
The actuator should drive fully open.
7. Remove the jumper from TR and N. The actuator
should drive fully closed.
8. Return EconoMi$er IV settings and wiring to normal
after completing troubleshooting.
Supply--Air Sensor
To check supply--air sensor input:
1. Make sure EconoMi$er IV preparation procedure has
been performed.
2. Set the Enthalpy potentiometer to A. The Free Cool
LED turns on. The actuator should drive to between
20 and 80% open.
3. Remove the 5.6 kilo--ohm resistor and jumper T to
T1. The actuator should drive fully open.
4. Remove the jumper across T and T1. The actuator
should drive fully closed.
5. Return EconoMi$er IV settings and wiring to normal
after completing troubleshooting.
EconoMi$er IV Troubleshooting
This procedure is used to return the EconoMi$er IV to
operation. No troubleshooting or testing is done by
performing the following procedure.
1. Disconnect power at TR and TR1.
2. Set enthalpy potentiometer to previous setting.
3. Set DCV maximum position potentiometer to previous setting.
4. Set minimum position, DCV setpoint, and exhaust potentiometers to previous settings.
5. Remove 620--ohm resistor from terminals SR and +.
6. Remove 1.2 kilo--ohm checkout resistor from terminals SO and +. If used, reconnect sensor from terminals SO and +.
7. Remove jumper from TR to N.
8. Remove jumper from TR to 1.
9. Remove 5.6 kilo--ohm resistor from T and T1. Reconnect wires at T and T1.
10. Remove jumper from P to P1. Reconnect device at P
and P1.
11. Apply power (24 vac) to terminals TR and TR1.
Input
Completion
WIRING DIAGRAMS
See Fig. 83 and Fig. 84 for typical wiring diagrams.
48TC
63
48TC
C08308
Fig. 83 -- 48TC Typical Unit Wiring Diagram -- Power (A06, 208/230--3--60)
64
C08317
48TC
65
Fig. 84 -- 48TC Unit Wiring Diagram -- Control (A06)
PRE--START-- UP
!
WARNING
PERSONAL INJURY HAZARD
Failure to follow this warning could result in personal
injury or death.
1. Follow recognized safety practices and wear protective goggles when checking or servicing refrigerant system.
2. Do not operate compressor or provide any electric
power to unit unless compressor terminal cover is
in place and secured.
3. Do not remove compressor terminal cover until
all electrical sources are disconnected.
48TC
4. Relieve all pressure from system before touching
or disturbing anything inside terminal box if refrigerant leak is suspected around compressor terminals.
5. Never attempt to repair soldered connection while
refrigerant system is under pressure.
6. Do not use torch to remove any component. System contains oil and refrigerant under pressure.
To remove a component, wear protective goggles
and proceed as follows:
a. Shut off electrical power and then gas to unit.
b. Recover refrigerant to relieve all pressure from
system using both high--pressure and low
pressure ports.
c. Cut component connection tubing with tubing
cutter and remove component from unit.
d. Carefully unsweat remaining tubing stubs
when necessary. Oil can ignite when exposed
to torch flame.
4. Verify the following conditions:
a. Make sure that condenser--fan blade are correctly
positioned in fan orifice. See Condenser--Fan
Adjustment section for more details.
b. Make sure that air filter(s) is in place.
c. Make sure that condensate drain trap is filled
with water to ensure proper drainage.
d. Make sure that all tools and miscellaneous loose
parts have been removed.
START--UP, GENERAL
Unit Preparation
Make sure that unit has been installed in accordance with
installation instructions and applicable codes.
Gas Piping
Check gas piping for leaks.
!
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could result in personal
injury or death.
Disconnect gas piping from unit when leak testing at
pressure greater than 1/2 psig. Pressures greater than
1/2 psig will cause gas valve damage resulting in
hazardous condition. If gas valve is subjected to
pressure greater than 1/2 psig, it must be replaced
before use. When pressure testing field--supplied gas
piping at pressures of 1/2 psig or less, a unit connected
to such piping must be isolated by manually closing
the gas valve.
Return--Air Filters
Proceed as follows to inspect and prepare the unit for
initial start--up:
1. Remove all access panels.
2. Read and follow instructions on all WARNING,
CAUTION, and INFORMATION labels attached to,
or shipped with, unit.
3. Make the following inspections:
a. Inspect for shipping and handling damages such
as broken lines, loose parts, or disconnected
wires, etc.
b. Inspect for oil at all refrigerant tubing connec-
tions and on unit base. Detecting oil generally
indicates a refrigerant leak. Leak--test all refrigerant tubing connections using electronic leak
detector, halide torch, or liquid--soap solution.
c. Inspect all field--wiring and factory--wiring con-
nections. Be sure that connections are completed
and tight. Be sure that wires are not in contact
with refrigerant tubing or sharp edges.
d. Inspect coil fins. If damaged during shipping and
handling, carefully straighten fins with a fin
comb.
Make sure correct filters are installed in unit (see
Appendix II -- Physical Data). Do not operate unit without
return--air filters.
Outdoor--Air Inlet Screens
Outdoor--air inlet screen must be in place before operating
unit.
Compressor Mounting
Compressors are internally spring mounted. Do not loosen
or remove compressor hold down bolts.
Internal Wiring
Check all electrical connections in unit control boxes.
Tighten as required.
Refrigerant Service Ports
Each unit system has two 1/4” SAE flare (with check
valves) service ports: one on the suction line, and one on
the compressor discharge line. Be sure that caps on the
ports are tight.
Compressor Rotation
On 3--phase units with scroll compressors, it is important
to be certain compressor is rotating in the proper
66
direction. To determine whether or not compressor is
rotating in the proper direction:
1. Connect service gauges to suction and discharge pressure fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge
pressure should rise, as is normal on any start--up.
If the suction pressure does not drop and the discharge
pressure does not rise to normal levels:
4. Note that the evaporator fan is probably also rotating
in the wrong direction.
5. Turn off power to the unit and install lockout tag.
6. Reverse any two of the unit power leads.
7. Re--energize to the compressor. Check pressures.
The suction and discharge pressure levels should now
move to their normal start--up levels.
NOTE: When the compressor is rotating in the wrong
direction, the unit will make an elevated level of noise
and will not provide cooling.
Cooling
Set space thermostat to OFF position. To start unit, turn on
main power supply. Set system selector switch at COOL
position and fan switch at AUTO. position. Adjust
thermostat toasetting belowroom temperature.
Compressor starts on closure of contactor.
Check unit charge. Refer to Refrigerant Charge section.
Reset thermostat at a position above room temperature.
Compressor will shut off. Evaporator fan will shut off
after a 30--second delay.
To shut off unit, set system selector switch at OFF
position. Resetting thermostat at a position above room
temperatureshuts unit off temporarilyuntil space
temperature exceeds thermostat setting.
Main Burners
Main burners are factory set and should require no
adjustment.
To check ignition of main burners and heating controls,
move thermostat setpoint above room temperature and
verify that the burners light and evaporator fan is
energized. Check heating effect, then lower the thermostat
setting below the room temperature and verify that the
burners and evaporator fan turn off.
Refer to Tables 11 and 12 for the correct orifice to use at
high altitudes.
Heating
1. Purge gas supply line of air by opening union ahead
of the gas valve. If gas odor is detected, tighten union
and wait 5 minutes before proceeding.
2. Turn on electrical supply and manual gas valve.
3. Set system switch selector at HEAT position and fan
switch at AUTO. or ON position. Set heating temperature lever above room temperature.
4. The induced--draft motor will start.
5. After a call for heating, the main burners should light
within 5 seconds. If the burner does not light, then
there is a 22--second delay before another 5--second
try. If the burner still does not light, the time delay is
repeated. If the burner does not light within 15
minutes, there is a lockout. To reset the control, break
the 24 v power to W1.
6. The evaporator--fan motor will turn on 45 seconds
after burner ignition.
7. The evaporator--fan motor will turn off in 45 seconds
after the thermostat temperature is satisfied.
8. Adjust airflow to obtain a temperature rise within the
range specified on the unit nameplate.
NOTE: The default value for the evaporator--fan motor
on/off delay is 45 seconds. The Integrated Gas Unit
Controller (IGC) modifies this value when abnormal limit
switch cycles occur. Based upon unit operating conditions,
the on delay can be reduced to 0 seconds and the off delay
can be extended to 180 seconds. When one flash of the
LED is observed, the evaporator--fan on/off delay has
been modified.
If the limit switch trips at the start of the heating cycle
during the evaporator on delay, the time period of the on
delay for the next cycle will be 5 seconds less than the
time at which the switch tripped. (Example: If the limit
switch trips at 30 seconds, the evaporator--fan on delay for
the next cycle will occur at 25 seconds.) To prevent
short--cycling, a 5--second reduction will only occur if a
minimum of 10 minutes has elapsed since the last call for
heating.
The evaporator--fan off delay can also be modified. Once
the call for heating has ended, there is a 10--minute period
during which the modification can occur. If the limit
switch trips during this period, the evaporator--fan off
delay will increase by 15 seconds. A maximum of 9 trips
can occur, extending the evaporator--fan off delay to 180
seconds.
To restore the original default value, reset the power to the
unit.
To shut off unit, set system selector switch at OFF
position. Resetting heating selector lever below room
temperature will temporarily shut unit off until space
temperature falls below thermostat setting.
Ventilation (Continuous Fan)
Set fan and system selector switches at ON and OFF
positions,respectively.Evaporatorfanoperates
continuously to provide constant air circulation. When the
evaporator--fan selector switch is turned to the OFF
position, there is a 30--second delay before the fan turns
off.
48TC
67
START--UP, PREMIERLINK CONTROLS
subsequent resets to factory defaults if the switch is left at
position 1.
!
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
The unit must be electrically grounded in accordance
with local codes and NEC ANSI/NFPA 70 (American
National Standards Institute/National Fire Protection
Association.)
Use the Carrier network communication software to start
up and configure the PremierLink controller.
Changes can be made using the ComfortWORKSr
software, ComfortVIEWt software, Network Service
48TC
Tool, System Pilott device, or Touch Pilott device. The
System Pilot and Touch Pilot are portable interface
devices that allow the user to change system set--up and
setpoints from a zone sensor or terminal control module.
During start--up, the Carrier software can also be used to
verify communication with PremierLink controller.
NOTE: All set--up and setpoint configurations are factory
set and field--adjustable.
For specific operating instructions, refer to the literature
provided with user interface software.
Perform System Check--Out
1. Check correctness and tightness of all power and
communication connections.
2. At the unit, check fan and system controls for proper
operation.
3. At the unit, check electrical system and connections
of any optional electric reheat coil.
4. Check to be sure the area around the unit is clear of
construction dirt and debris.
5. Check that final filters are installed in the unit. Dust
and debris can adversely affect system operation.
6. Verify that the PremierLink controls are properly connected to the CCN bus.
Initial Operation and Test
Perform the following procedure:
1. Apply 24 vac power to the control.
2. Connect the service tool to the phone jack service
port of the controller.
3. Using the Service Tool, upload the controller from
address 0, 31 at 9600 baud rate. The address may be
set at this time. Make sure that Service Tool is connected to only one unit when changing the address.
Memory
DIP switch 4 causes an E--squared memory reset to
factory defaults after the switch has been moved from
position 0 to position 1 and the power has been restored.
To enable the feature again, the switch must be put back
to the 0 position and power must be restored; this prevents
Reset
To cause a reset of the non--volatile memory (to factory
defaults), turn the controller power off if it is on, move the
switch from position 1 to position 0, and then apply power
to the controller for a minimum of 5 seconds. At this
point, no action occurs, but the controller is now ready for
the memory to reset. Remove power to the controller
again and move the switch from position 0 to position 1.
This time, when power is applied, the memory will reset
to factory defaults. The controller address will return to
bus 0 element 31, indicating that memory reset occurred.
Refer to Installation Instruction 33CS--58SI for full
discussion on configuring the PremierLink control system.
START--UP, RTU--MP CONTROL
Field Service Test, explained below, will assist in proper
start--up. Configuration of unit parameters, scheduling
options, and operation are also discussed in this section.
Field Service Test
The Field Service Test function can be used to verify
proper operation of compressors, heating stages, indoor
fan,powerexhaustfans,economizer,and
dehumidification.UseofFieldServiceTestis
recommended at initial system start up and during
troubleshooting. See Form 48--50H--T--2T, Appendix A for
Field Service Test Mode table.
Field Service Test mode has the following changes from
normal operation:
S Outdoor air temperature limits for cooling circuits,
economizer, and heating are ignored.
S Normal compressor time guards and other staging delays
are ignored.
S The status of Alarms (except Fire and Safety chain) is
ignored but all alerts and alarms are still broadcasted on
the network.
Field Service Test can be turned ON/OFF at the unit
display or from the network. Once turned ON, other
entries may be made with the display or through the
network. To turn Field Service Test on, change the value
of Test Mode to ON, to turn Field Service Test off, change
the value of Test Mode to OFF.
NOTE: Service Test mode is password protected when
accessing from the display. Depending on the unit model,
factory--installed options, and field--installed accessories,
some of the Field Service Test functions may not apply.
The independent outputs (IndpOutputs) submenu is used
to change output status for the supply fan, economizer,
and Power Exhaust. These independent outputs can
operate simultaneously with other Field Service Test
modes. All outputs return to normal operation when Field
Service Test is turned off.
The Cooling submenu is used to change output status for
the individual compressors and the dehumidification relay.
Compressor starts are not staggered. The fans and heating
service test outputs are reset to OFF for the cooling
service test. Indoor fans and outdoor fans are controlled
68
normally to maintain proper unit operation. All normal
cooling alarms and alerts are functional.
NOTE: Circuit A is always operated with Circuit B due
to outdoor fan control on Circuit A. Always test Circuit A
first, and leave it on to test other Circuits.
The Heating submenu is used to change output status for
the individual heat stages, gas or electric. The fans and
cooling service test outputs are reset to OFF for the
heating service test. All normal heating alarms and alerts
are functional.
Configuration
The RTU--MP controller configuration points affect the
unit operation and/or control. Review and understand the
meaning and purpose of each configuration point before
changing it from the factory default value. The submenus
containing configuration points are as follows: Unit,
Cooling, Heating, Inputs, Economizer, IAQ, Clock--Set,
and User Password (USERPW). Each configuration point
is described below under its according submenu. See
Form 48--50H--T--2T, Appendix for display tables.
Unit
Start Delay
This refers to the time delay the unit will wait after power
up before it pursues any specific operation.
Factory Default = 5 sec
Range = 0--600 sec
Filter Service Hours
This refers to the timer set for the Dirty Filter Alarm.
After the number of runtime hours set on this point is
exceeded the corresponding alarm will be generated, and
must be manually cleared on the alarm reset screen after
the maintenance has been completed. The timer will then
begin counting its runtime again for the next maintenance
interval.
Factory Default = 600 hr
NOTE: Setting this configuration timer to 0, disables the
alarm.
Supply Fan Service Hours
This refers to the timer set for the Supply Fan Runtime
Alarm. After the number of runtime hours set on this point
is exceeded the corresponding alarm will be generated,
and must be manually cleared on the alarm reset screen
after the maintenance has been completed. The timer will
then begin counting its runtime again for the next
maintenance interval.
Factory Default = 0 hr
NOTE: Setting this configuration timer to 0, disables the
alarm.
Compressor1 Service Hours
This refers to the timer set for the Compressor 1 Runtime
Alarm. After the number of runtime hours set on this point
is exceeded the corresponding alarm will be generated,
and must be manually cleared on the alarm reset screen
after the maintenance has been completed. The timer will
then begin counting its runtime again for the next
maintenance interval.
Factory Default = 0 hr
NOTE: Setting this configuration timer to 0, disables the
alarm.
Compressor2 Service Hours
This refers to the timer set for the Compressor 2 Runtime
Alarm. After the number of hours set on this point is
exceeded the corresponding alarm will be generated, and
must be manually cleared on the alarm rest screen after
the maintenance has been completed. The timer will then
begin counting its runtime again for the next maintenance
interval
Factory Default = 0 hr
NOTE: Setting this configuration timer to 0, disables the
alarm.
Cooling
Number of Compressor Stages
This refers to the number of mechanical cooling stages
available on a specific unit. Set this point to “One Stage”
if there is one compressor in the specific unit, set to “Two
Stage” if there are two compressors in the unit, and set to
“None” if economizer cooling ONLY is desired.
Factory Default = One Stage for 1 compressor units
Two Stage for 2 compressor units
Cooling/Econ SAT Low Setpt
The supply air temperature must remain above this value
to allow cooling with the economizer and/or compressors.
There is 5_F plus and minus deadband to this point. If the
SAT falls below this value during cooling, all compressors
will be staged off. The economizer will start to ramp
down to minimum position when the SAT = this
configuration +5_F.
Factory Default = 50_F
Range = 45--75_F
Cooling Lockout Temp
This defines the minimum outdoor air temperature that
cooling mode can be enabled and run. If the OAT falls
below this threshold during cooling, then compressor
cooling will not be allowed.
Factory Default = 45_F
Range = 0--65_F
Heating
Heating SAT High Setpt
The supply air temperature must remain below this value
to allow heating. There is 5_F plus and minus deadband to
this point. If the SAT rises above this value during heating
the heat stages will begin to decrease until the SAT has
dropped below this value.
Factory Default = 120_F
Range = 95--150_F
Heating Lockout Temp
This defines the maximum outdoor air temperature that
heating mode can be enabled and run. If the OAT rises
above this threshold during heating, then heating will not
be allowed.
Factory Default = 65_F
Range = 49--95_F
48TC
69
Inputs
NOTE:For installation of inputs and field installed
accessories, refer to the appropriate sections.
Input 3
This input is a discrete input and can be configured to be
one of five different inputs: No Function, Compressor
Safety, Fan Status, Filter Status, or Remote Occupancy.
This input can also be configured to be either Normally
Open (N/O) or Normally Closed (N/C). Input 3 is factory
wired to pin J1--2. Field accessories get wired to its
parallel pin J5--5. Do not connect inputs to both locations,
one function per input.
Factory Default = Compressor Safety and N/O
NOTE: Compressor Safety input comes from the CLO
board. J1--2 is always factory wired to TB1--8 (X) terminal
on the unit. If the unit has a CLO board, do not configure
input 3 for anything but Compressor Safety.
48TC
Input 5
This input is a discrete input and can be configured to be
one of five different inputs: No Function, Fire Shutdown,
Fan Status, Filter Status, or Remote Occupancy. This
input can also be configured to be either Normally Open
(N/O) or Normally Closed (N/C). Input 5 is factory wired
to pin J1--10. Field accessories get wired to its parallel pin
J5--3. Do not connect inputs to both locations, one
function per input.
Factory Default = Fire Shutdown and N/C
NOTE: Fire Shutdown input comes from TB4--7. J1--10
is always factory wired to TB4--7. Only change input 5s
function if absolutely needed.
Input 8
This input is a discrete input and can be configured to be
one of five different inputs: No Function, Enthalpy
Switch, Fan Status, Filter Status, or Remote Occupancy.
This input can also be configured to be either Normally
Open (N/O) or Normally Closed (N/C). Input 8 is factory
wired to pin J2--6. Field accessories get wired to its
parallel pin J5--1. Do not connect inputs to both locations,
one function per input.
Factory Default = No Function and N/O
Input 9
This input is a discrete input and can be configured to be
one of five different inputs: No Function, Humidistat, Fan
Status, Filter Status, or Remote Occupancy. This input can
also be configured to be either Normally Open (N/O) or
Normally Closed (N/C). Input 9 is factory and field wired
to pin J5--7. Do not connect inputs to both locations, one
function per input.
Factory Default = Humidistat and N/O
Space Sensor Type
This tells the controller what type of space sensor is
installed to run the unit. The three types that can be used
are the T55 space sensor, the T56 space sensor, or the RS
space sensor.
Factory Default = T55 Type
Input 1 Function
This input is an analog input and can be configured to be
one of five different inputs: No Sensor, IAQ Sensor, OAQ
Sensor, Space RH Sensor, or Outdoor RH Sensor. Input 1
iswiredtopinJ4--5.
Factory Default = No Sensor
Input 2 Function
This input is an analog input and can be configured to be
one of five different inputs: No Sensor, IAQ Sensor, OAQ
Sensor, Space RH Sensor, or Outdoor RH Sensor. Input 2
iswiredtopinJ4--2.
Factory Default = No Sensor
Setpoint Slider Range
This sets the slider range of the space sensor (with this
built in function). The slider is used to offset the current
control setpoint.
Factory Default = 5 n_F
Range = 0--15 n_F
T55/56 Override Duration
This sets the occupancy override duration when the
override button is pushed on the space sensor.
Factory Default = 1 hr
Range = 0--24 hr
IAQ Low Reference @ 4mA
This is used when an IAQ sensor is installed on Input 1 or
2. This value is displayed and used when 4mA is seen at
the input.
Factory Default = 0 PPM
Range = 0--400 PPM
IAQ High Reference @ 20mA
This is used when an IAQ sensor is installed on Input 1 or
2. This value is displayed and used when 20mA is seen at
the input.
Factory Default = 2000 PPM
Range = 0--5000 PPM
NOTE:IAQ low Reference @ 4mA and IAQ High
Reference @ 20mA are used to set the linear curve of mA
vs. PPM.
OAQ Low Reference @ 4mA
This is used when an OAQ sensor is installed on Input 1
or 2. This value is displayed and used when 4mA is seen
at the input.
Factory Default = 0 PPM
Range = 0--400 PPM
OAQ High Reference @ 20mA
This is used when an OAQ sensor is installed on Input 1
or 2. This value is displayed and used when 20mA is seen
at the input.
Factory Default = 2000 PPM
Range = 0--5000 PPM
NOTE:OAQ low Reference @ 4mA and OAQ High
Reference @ 20mA are used to set the linear curve of mA
vs. PPM.
70
Economizer
Economizer Exists
This point tells the controller if there is an economizer
installed on the unit.
Factory Default = NO if no economizer
YES if there is an economizer installed
Economizer Minimum Position
This defines the lowest economizer position when the
indoor fan is running and the building is occupied.
Factory Default = 20%
Range = 0--100 %
Economizer High OAT Lockout
If the outdoor air temperature rises above this value,
economizer cooling will be disabled and dampers will
return and stay at minimum position.
Factory Default = 75_F
Range = 55--80_F
Power Exhaust Setpt
When the economizer damper position opens above this
point the power exhaust operation will begin. When the
damper position falls 10% below the setpoint, the power
exhaust will shutdown.
Factory Default = 50%
Range = 20--90 %
NOTE: This point is only used when Continuous Occ
Exhaust = NO
Continuous Occ Exhaust
This point tells the controller when to run the power
exhaust if equipped on the unit. If set to YES, the power
exhaust will be on all the time when in occupied mode
and will be off when in unoccupied mode. If set to NO the
power exhaust will be controlled by the Power Exhaust
Setpoint.
Factory Default = NO
IAQ
Max Differential CO
If the difference between indoor an outdoor air quality
becomes greater then this value the damper position will
stay at the IAQ Greatest Min Dmpr Pos. configuration
point
Factory Default = 650 PPM
Range = 300--950 PPM
IAQ Greatest Min Dmpr Pos.
This is the greatest minimum position the economizer will
open to while trying to control the indoor air quality, CO
differential.
Factory Default = 50% open
Range = 10--60% open
Clockset
This submenu screen allows you to set the date and time
manually. The Daylight Savings Time (DST) can also be
changed here. The date and time is automatically set when
ever software is downloaded. The clock is a 24 hour clock
and not am/pm. The time should be verified (and maybe
changed) according to unit location and time zone.
Factory Default = Eastern Standard Time
Setpt
2
USERPW
This submenu screen allows you to change the user
password to a four number password of choice. The User
password change screen is only accessible with the
Administrator Password (1111). The ADMIN password
will always override the user password.
OPERATING SEQUENCES
Base Unit Controls
Cooling, Units Without Economizer
When thermostat calls for cooling, terminals G and Y1 are
energized.Theindoor--fancontactor(IFC)and
compressor contactor are energized and indoor--fan motor,
compressor, and outdoor fan starts. The outdoor fan motor
runs continuously while unit is cooling.
Heating, Units Without Economizer
When the thermostat calls for heating, terminal W1 is
energized. To prevent thermostat short--cycling, the unit is
locked into the Heating mode for at least 1 minute when
W1 is energized. The induced--draft motor is energized
and the burner ignition sequence begins. The indoor
(evaporator) fan motor (IFM) is energized 45 seconds
after a flame is ignited. On units equipped for two stages
of heat, when additional heat is needed, W2 is energized
and the high--fire solenoid on the main gas valve (MGV)
is energized. When the thermostat is satisfied and W1 is
deenergized, the IFM stops after a 45--second time off
delay.
Cooling, Unit With EconoMi$er IV
For Occupied mode operation of EconoMi$er IV, there
must be a 24--v signal at terminals TR and N (provided
through PL6--3 from the unit’s IFC coil). Removing the
signal at N places the EconoMi$er IV control in
Unoccupied mode.
During Occupied mode operation, indoor fan operation
will be accompanied by economizer dampers moving to
Minimum Position setpoint for ventilation. If indoor fan is
off, dampers will close. During Unoccupied mode
operation, dampers will remain closed unless a Cooling
(by free cooling) or DCV demand is received.
Integrated EconoMi$er IV operation on 48TC single
compressor model requires a 2--stage thermostat (Y1 and
Y2 switches).
When free cooling using outside air is not available, the
2
unit cooling sequence will be controlled directly by the
space thermostat as described above as Cooling, Without
Economizer. Outside air damper position will be closed or
Minimum Position as determined by occupancy mode and
fan signal.
When free cooling is available as determined by the
appropriate changeover command (dry bulb, outdoor
enthalpy, differential dry bulb or differential enthalpy), a
call for cooling (Y1 closes at the thermostat) will cause
the economizer control to modulate the dampers open and
closed to maintain the unit supply air temperature at 50 to
55_F. Compressor will not run.
48TC
71
During free cooling operation, a supply air temperature
(SAT) above 50_F will cause the dampers to modulate
between Minimum Position setpoint and 100% open. With
SAT from 50_Fto45_F, the dampers will maintain at the
Minimum Position setting. With SAT below 45_F, t he
outside air dampers will be closed. When SAT rises to
48_F, the dampers will re--open to Minimum Position
setting.
Should 100% outside air not be capable of satisfying the
space temperature, space temperature will rise until Y2 is
closed. The economizer control will call for compressor
operation. Dampers will modulate to maintain SAT at 50
to 55_F concurrent with compressor operation. The Low
Ambient Lockout Thermostat will block compressor
operation with economizer operation below 42_F outside
air temperature.
When space temperature demand is satisfied (thermostat
48TC
Y1 opens), the dampers will return to Minimum Damper
position if indoor fan is running or fully closed if fan is
off.
If accessory power exhaust is installed, the power exhaust
fan motors will be energized by the economizer control as
the dampers open above the PE--On setpoint and will be
de--energized as the dampers close below the PE--On
setpoint.
Damper movement from full closed to full open (or vice
versa) will take between 1--1/2 and 2--1/2 minutes.
Heating With EconoMi$er IV
During Occupied mode operation, indoor fan operation
will be accompanied by economizer dampers moving to
Minimum Position setpoint for ventilation. If indoor fan is
off, dampers will close. During Unoccupied mode
operation, dampers will remain closed unless a DCV
demand is received.
When the room temperature calls for heat (W1 closes), the
heating controls are energized as described in Heating,
Unit Without Economizer above.
PremierLink Control
THERMOSTAT MODE — If the PremierLink controller
is configured for Thermostat mode (TSTAT), it will
control only to the thermostat inputs on J4. These inputs
can be overridden through CCN communication via the
CV_TSTAT points display table. When in this mode, the
fire safety shutdown (FSD) input cannot be used, so any
fire/life safety shutdown must be physically wired to
disable the 24 vac control circuit to the unit.
Indoor Fan — The indoor fan output will be energized
whenever there is 24 vac present on the G input. The
indoor fan will be turned on without any delay and the
economizer damper will open to its minimum position if
the unit has a damper connected to the controller. This
will also occur if the PremierLink controller has been
configured for electric heat or heat pump operation.
Cooling — For cooling operation, there must be 24 vac
present on G. When G is active, the PremierLink
controller will then determine if outdoor conditions are
suitable for economizer cooling when an economizer
damper is available. A valid OAT, SPT (CCN space
temperature) and SAT (supply air temperature) sensor
MUST be installed for proper economizer operation. It
recommended that an outdoor or differential enthalpy
sensor also be installed. If one is not present, then a
jumper is needed on the ENTH input on J4, which will
indicate that the enthalpy will always be low. Economizer
operation will be based only on outdoor air dry bulb
temperature. The conditions are suitable when: enthalpy is
low, OAT is less than OATL High Lockout for TSTAT,
and OAT is less than OATMAX, the high setpoint for free
cooling. The default for OATL is 65_F. The default for
OATMAX is 75_F.
When all of the above conditions are satisfied and all the
required sensors are installed, the PremierLink controller
will use the economizer for cooling. One of three different
controlroutineswillbeused dependingonthe
temperature of the outside air. The routines use a PID loop
to control the SAT to a supply air setpoint (SASP) based
on the error from setpoint (SASPSAT). The SASP is
determined by the routine.
If an economizer is not available or the conditions are not
met for the following economizer routines below, the
compressors 1 and 2 will be cycled based on Y1 and Y2
inputs respectively.
Any time the compressors are running, the PremierLink
controller will lock out the compressors if the SAT
becomes too low. These user configurable settings are
found in the SERVICE configuration table:
Compressor 1 Lockout at SAT < SATLO1 (50 to 65_F)
(default is 55_F)
Compressor 2 Lockout at SAT < SATLO2 (45 to 55_F)
(default is 50_F)
After a compressor is locked out, it may be started again
after a normal time--guard period and the supply--air
temperature has increased at least 8_F above the lockout
setpoint.
Routine No. 1: If the OAT ≤ DXLOCK (OAT DX lockout
temperature) and DX Cooling Lockout is enabled when
Y1 input is energized, the economizer will be modulated
to maintain SAT at the Supply Air Setpoint (SASP) =
SATLO1 + 3_F (Supply Air Low Temp lockout for
compressor 1). When Y2 is energized, the economizer
will be modulated to control to a lower SASP = SATLO2
+3_F (Supply Air Low Temp lockout for compressor no.
2). Mechanical cooling is locked out and will not be
energized.
Routine No. 2: If DXLOCK (or DX Cooling Lockout is
disabled) < OAT ≤ 68_F when Y1 input is energized, the
economizer will be modulated to maintain SAT at SASP =
SATLO1 + 3_F. If t he SAT > SASP + 5_F and the
economizer position > 85% then the economizer will
close the to minimum position for three minutes or until
the SAT > 68_F. The economizer integrator will then be
reset and begin modulating to maintain the SASP after
stage one has been energized for 90 seconds.
72
When Y2 is energized, the economizer will be modulated
to control to a lower supply air setpoint SASP= SATLO2
+3_F If the SAT > SASP + 5_F it will close the
economizer to minimum position for 3 minutes, reset the
integrator for the economizer, then start modulating the
economizer to maintain the SASP after the stage two has
been on for 90 seconds. This provides protection for the
compressor against flooded starts and allow refrigerant
flow to stabilize before modulating the economizer again.
By using return air across the evaporator coil just after the
compressor has started allows for increased refrigerant
flow rates providing better oil return of any oil washed out
during compressor start--up.
Routine No. 3: If the OAT > 68_F and the enthalpy is low
and the OAT < SPT then the economizer will open to
100% and compressors 1 and 2 will be cycled based on
Y1 and Y2 inputs respectively. If any of these conditions
are not met the economizer will go to minimum position.
If there is no call for heating or cooling, the economizer,
if available, will maintain the SASP at 70_F.
Heating — For gas or electric heat, HS1 and HS2 outputs
will follow W1 and W2 inputs respectively. The fan will
also be turned on if it is configured for electric heat.
Heating may also be energized when an IAQ sensor
installed and has overridden the minimum economizer
damper position. If the OAT < 55_F and an IAQ sensor is
installed and the IAQ minimum position > minimum
damper position causing the SAT to decrease below the
SPT -- 10_F, then the heat stages will be cycled to temper
the SAT to maintain a temperature between the SPT and
the SPT + 10_F.
Auxiliary Relay configured for Exhaust Fan — If the
Auxiliary Relay is configured for exhaust fan (AUXOUT
= 1) in the CONFIG configuration table and Continuous
Power Exhaust (MODPE) is enable in the SERVICE
configuration table then the output (HS3) will be
energized whenever the G input is on. If the MODPE is
disabled then output will be energized based on the Power
Exhaust Setpoint (PES) in the SETPOINT table.
Indoor Air Quality — If the optional indoor air quality
(IAQI) sensor is installed, the PremierLink controller will
maintain indoor air quality within the space at the
user--configured differential setpoint (IAQD) in the
CONFIG configurationtable.Thesetpoint isthe
difference between the IAQI and an optional outdoor air
quality sensor (OAQ). If the OAQ is not present then a
fixed value of 400 ppm is used. The actual space IAQ
setpoint (IAQS) is calculated as follows:
IAQS = IAQD + OAQ (OAQ = 400 ppm if not present)
As air quality within the space changes, the minimum
position of the economizer damper will be changed also
thus allowing more or less outdoor air into the space
depending on the relationship of the IAQI to the IAQS.
The IAQ algorithm runs every 30 seconds and calculates
IAQ minimum position value using a PID loop on the
IAQI deviation from the IAQS. The IAQ minimum
position is then compared against the user configured
minimum position (MDP) and the greatest value becomes
the final minimum damper position (IQMP). If the
calculated IAQ Minimum Position is greater than the IAQ
maximum damper position (IAQMAXP) decision in the
SERVICE configuration table, then it will be clamped to
IAQMAXP value.
If IAQ is configured for low priority, the positioning of
the economizer damper can be overridden by comfort
requirements. If the SAT < SASP --8_F and both stages of
heat are on for more then 4 minutes or the SAT > SASP +
5_F and both stages of cooling on for more then 4 minutes
then the IAQ minimum damper position will become 0
and the IQMP = MDP. IAQ mode will resume when the
SAT > SASP --8_F in heating or the SAT < SASP + 5_Fin
cooling.
If the PremierLink controller is configured for 1 stage of
heat and cool or is only using a single stage thermostat
input, this function will not work as it requires the both
Y1 and Y2 or W1 and W2 inputs to be active. In this
application, it is recommended that the user configure
IAQ priority for high.
If IAQ is configured for high priority and the OAT < 55_F
and the SAT < (SPT --10_F), the algorithm will enable the
heat stages to maintain the SAT between the SPT and the
SPT + 10_F.
CCN SENSOR MODE — When the PremierLink
controller is configured for CCN control, it will control
the compressor, economizer and heating outputs based its
own space temperature input and setpoints or those
received from Linkage. An optional CO
IAQ sensor
2
mounted in the space or received through communications
can also influence the economizer and heating outputs.
The PremierLink controller does not have a hardware
clock so it must have another device on the CCN
communication bus broadcasting time. The controller will
maintain its own time once it has received time as long as
it has power and will send a request for time once a
minute until it receives time when it has lost power and
power is restored. Thecontroller willcontrol to
unoccupied setpoints until it has received a valid time.
The controller must have valid time in order to perform
any broadcast function, follow an occupancy schedule,
perform IAQ pre--occupancy purge and many other
functions as well. The following sections describe the
operation for the functions of the PremierLink controller.
Indoor Fan — The indoor fan will be turned on whenever
any one of the following conditions are met:
S If the PremierLink controller is in the occupied mode and
ASHRAE 90.1 Supply Fan is configured for Yes in the
CONFIG table. This will be determined by its own
internal occupancy schedule if it is programmed to
follow its local schedule or broadcast its local schedule as
a global schedule, or following a global schedule
broadcast by another device.
S If PremierLink controller is in the occupied mode and
ASHRAE 90.1 Supply Fan is configured for No and there
is a heat or cool demand (fan auto mode)
48TC
73
S If the PremierLink controller is in the occupied mode and
ASHRAE 90.1 Supply Fan is configured for Yes when
Linkage is active and the Linkage Coordinator device is
sending an occupied mode flag
S When Temperature Compensated Start is active
S When Free Cool is active
S When Pre--Occupancy Purge is active
S Whenever there is a demand for cooling or heating in the
unoccupied mode
S Whenever the Remote Contact input is configured for
Remote Contact (RC_DC=1 in SERVICE table) and it is
closed or the point is forced Closed via communications
in the STATUS01 points display table (remote contact
closed = occupied, remote contact open = unoccupied)
S Whenever the H3_EX_RV point is configured for
Dehumidification (AUXOUT=5 in CONFIG table) and it
48TC
is in the unoccupied mode and the indoor RH exceeds the
unoccupied humidity setpoint
S Whenever the Supply Fan Relay point is forced On in the
STATUS01 points display table
The fan will also continue to run as long as compressors
are on when transitioning from occupied to unoccupied
with the exception of Fire Shutdown mode. If the Fire
Shutdown input point is closed or forced in the
STATUS01 points display table, the fan will be shutdown
immediately regardless of the occupancy state or demand.
The PremierLink controller has an optional Supply Fan
Status input to provide proof of airflow. If this is enabled,
the point will look for a contact closure whenever the
Supply Fan Relay is on. If the input is not enabled, then it
will always be the same state as the Supply Fan Relay.
The cooling, economizer and heating routines will use this
input point for fan status.
Cooling — The compressors are controlled by the Cooling
Control Loop that is used to calculate the desired SAT
needed to satisfy the space. It will compare the SPT to the
Occupied Cool Setpoint (OCSP) + the T56 slider offset
(STO) when occupied and the Unoccupied Cool Setpoint
(UCSP + Unoccupied Cooling Deadband) if unoccupied
to calculate a Cooling Submaster Reference (CCSR) that
is then used by the staging algorithm (Cooling submaster
loop) to calculate the required number of cooling stages.
The economizer, if available, will be used as the first
stage of cooling in addition to the compressors. This loop
runs every minute. The following conditions must be met
in order for this algorithm to run:
S indoor fan has been ON for at least 30 seconds
S heat mode is not active and the time guard between
modes equals zero.
S mode is occupied or the Temperature Compensated Start
or Cool mode is active
S SPT reading is available and > (OCSP + STO)
S If mode is unoccupied and the SPT > (UCSP +
Unoccupied Cooling Deadband). The indoor fan will be
turned on by the staging algorithm.
S OAT > DXLOCK or OAT DX Lockout is disabled
If all of the above conditions are met, the CCSR will be
calculated, otherwise it is set to its maximum value and
DX stages is set to 0. If only the last condition is not true
and an economizer is available, it will be used to cool the
space.
The submaster loop uses the CCSR compared to the actual
SAT to determine the required number of capacity stages
to satisfy the load. There is a programmable minimum
internal time delay of 3 to 5 minutes on and 2 to 5 minutes
off for the compressors to prevent short cycling. There is
also a 3--minute time delay before bringing on the second
stage compressor. If the PremierLink controller is
configured for Heat Pump and AUXOUT is configured for
Reversing Valve Cool, the H3_EX_RV output will
energize 2 seconds after the first compressor is energized
and stay energized until there is a demand for heat. If
AUXOUT is configured for Reversing Valve Heat, then
the H3_EX_RV contact will be deenergized when there is
a demand for cooling. An internal 5 to 10--minute
user--programmable time guard between modes prevents
rapid cycling between modes when used in a single zone
application. The Time Guard is lowered to 3 minutes
when Linkage is active to allow the 3Vt linkage
coordinator to have better control of the PremierLink
controller when used as the air source for the 3V control
system.
Table 29 indicates the number of stages available. The
staging algorithm looks at the number of stages available
based the number of cool stages configured in the
SERVICE configuration table. The algorithm will skip the
economizer if it is not available and turn on a compressor.
Table 29 – Available Cooling Stages
NUMBER OF
STAGES
Compressor 1OffOffOnOn
Compressor 2OffOffOffOn
* If conditions are suitable for economizer operation.
0
(ECONOMIZER*)
1
23
Any time the compressors are running, the PremierLink
controller will lockout the compressors if the SAT
becomes too low. These user configurable settings are
found in the SERVICE configuration table:
Compressor 1 Lockout at SAT < SATLO1 (50 to 65_F)
(default is 55_F)
Compressor 2 Lockout at SAT < SATLO2 (45 to 55_F)
(default is 50_F)
After a compressor is locked out, it may be started again
after a normal time--guard period and the supply air
temperature has increased at least 8_F above the lockout
setpoint.
Dehumidification — The PremierLink controller will
provideoccupiedandunoccupieddehumidification
control when AUXOUT = 5 in the CONFIG table and is
installed on HVAC units that are equipped with additional
controls and accessories to accomplish this function. This
function also requires a space relative humidity sensor be
installed on the OAQ/IRH input.
74
When in the occupied mode and the indoor relative
humidity is greater then the Occupied High Humidity
setpoint, then the H3_EX_RV output point will be
energized. When in the unoccupied mode and indoor
relative humidity is greater then the Unoccupied High
Humidity setpoint, then the H3_EX_RV output point and
supply fan output will be energized. There is a fixed 5%
hysteresis that the indoor relative humidity must drop
below the active setpoint to end the dehumidification
mode and deenergize the H3_EX_RV output. If the
PremierLink controller is in the unoccupied mode, then
the fan relay will deenergize if there is no other mode
requiring to the fan to be on. This function will not
energize mechanical cooling as a result of the indoor
relative humidity exceeding either setpoint.
A high humidity alarm will be generated if the indoor
relative humidity exceeds the high humidity setpoint by
the amount configured in the Control Humidity Hysteresis
in the ALARMS table for 20 minutes. The alarm will
return to normal when the indoor relative humidity drops
3% below the active humidity setpoint.
Economizer — The economizer dampers are used to
provide free cooling and indoor air quality if optional CO
sensor is installed and when the outside conditions are
suitable.Temperaturecontrolisaccomplishedby
controlling the SAT to a certain level determined by the
Economizer PID Loop by calculating a submaster
reference (ECONSR) value. This algorithm will calculate
the submaster reference temperature (ECONSR) based on
OAT and enthalpy conditions and cooling requirements.
The ECONSR value is then passed to the Economizer
Submaster Loop, which will modulate dampers to
maintain SAT at ECONSR level.
The actual damper position (ECONPOS) is the result of
the following calculation. Values represented in the right
side of the equation can be found in the SERVICE
configuration table descriptions in this manual. Note that
that the OAT is taken into consideration to avoid large
changes in damper position when the OAT is cold:
ECONPOS = SubGain x (ECONSR--SAT) + CTRVAL
where SubGain = (OAT -- TEMPBAND) / (ESG + 1)
If the OAT < DXLOCK (DX Cool Lockout setpoint) then
the damper will be modulated to maintain the SAT at the
ECONSR value.
If the OAT is between DXLOCK and 68_F (DXLOCK <
OAT < 68_F) and additional cooling is required, the
economizer will close the to minimum position for three
minutes, the economizer integrator will then be reset to 0
and begin modulating to maintain the SASP after the stage
has been energized for about 90 seconds. This will allow
the economizer to calculate a new ECONSR that takes
into account the cooling effect that has just been turned on
and not return to the value require before the cooling was
added. This will prevent the economizer from causing
premature off cycles of compressors while maintaining the
2
low SAT temperature setpoint for the number of stages
active. In addition to preventing compressor short cycling,
by using return air across the evaporator coil just after the
compressor has started allows for increased refrigerant
flow rates providing for better oil return of any oil washed
out during compressor start--up.
If the OAT > 68_F and OAT < SPT and the number of DX
stages requested is > 0 by the staging algorithm, then
ECONSR is set to its minimum value 48_F and the
damper will go to 100% open.
48TC
The following conditions are required to determine if
economizer cooling is possible:
S Indoor fan has been on for at least 30 seconds
S Enthalpy is low
S SAT reading is available
S OAT reading is available
S SPT reading is available
S OAT ≤ SPT
S OAT < OATMAX (OATMAX default is 75_F)
S Economizer position is NOT forced
If any of the above conditions are not met, the ECONSR
will be set to its MAX limit of 120_F and the damper will
go to its configured minimum position. The minimum
damper position can be overridden by the IAQ routine
described later in this section.
The calculation for ECONSR is as follows:
ECONSR = PID function on (setpoint -- SPT), where:
setpoint = ((OCSP+STO) + (OHSP+STO))/2 when
setpoint = (OCSP+STO) -- 1 when OAT ≤ NTLO
setpoint = (OHSP+STO) + 1 when OAT ≥ 68_F
If the Auxiliary Relay is configured for exhaust fan
(AUXOUT = 1) in the CONFIG configuration table and
Continuous Power Exhaust (MODPE) is Enable in the
SERVICE configuration table, then the AUXO output
(HS3) will be energized whenever the PremierLink
controller is in the occupied mode. If the MODPE is
disabled then AUXO output will be energized based on
the Power Exhaust Setpoint (PES) in the SETPOINT
table.
Heating — The heat stages are controlled by the Heating
Control Loop, which is used to calculate the desired SAT
needed to satisfy the space. It will compare the SPT to the
Occupied Heat Setpoint (OHSP) + the T56 slider offset
(STO) when occupied and the Unoccupied Heat Setpoint
(UHSP -- Unoccupied Heating Deadband) if unoccupied to
calculate a Staged Heat Submaster Reference (SHSR).
The heat staging algorithm compares the SHSR to the
actual SAT to calculate the required number of heating
stages to satisfy the load. This loop runs every 40 seconds.
The following conditions must be met in order for this
algorithm to run:
S Indoor fan has been ON for at least 30 seconds.
S Cool mode is not active and the time guard between
modes equals zero.
S Mode is occupied or the Temperature Compensated Start
or Heat mode is active.
75
S SPT reading is available and < (OHSP + STO).
S If it is unoccupied and the SPT < (UHSP -- Unoccupied
Heating Deadband). The indoor fan will be turn on by the
staging algorithm.
When all of the above conditions are met, the SHSR is
calculated and up to 3 stages of heat will turned on and off
to satisfy to maintain the SAT = SHSR. If any of the
above conditions are not met, the SHSR is set to its
minimum value of 35_F.
The Staged Heat Submaster Reference (SHSR) is
calculated as follows:
SHSR = Heating PID function on (error) where error =
(OHSP + STO) -- Space Temperature
The Maximum SHSR is determined by the SATHI
configuration. If the supply--air temperature exceeds the
SATHI configuration value, then the heat stages will turn
48TC
off. Heat staging will resume after a delay to allow the
supply--air temperature to drop below the SATHI value.
The maximum number of stages available is dependent on
the type of heat and the number of stages programmed in
the CONFIG and SERVICE configuration tables. Staging
will occur as follows for gas electric units, Carrier heat
pumps with a defrost board, or cooling units with electric
heat:
Staging will occur as follows For heat pump units with
AUXOUT configured as reversing valve:
For Heating PID STAGES = 2 and AUXOUT = Reversing
Valve Heat (the H3_EX_RV output will stay energized
until there is a cool demand) HEAT STAGES = 1 (50%
capacity) shall energize CMP1, CMP2, RVS.
Heating PID STAGES = 3 and AUXOUT = Reversing
Valve Heat (the H3_EX_RV output will stay energized
until there is a cool demand)
S an IAQ sensor is installed
S the IAQ Minimum Damper Position > minimum damper
position
S and the SAT < SPT --10_F.
There is also a SAT tempering routine that will act as SAT
low limit safety to prevent the SAT from becoming too
cold should the economizer fail to close. One stage of
heating will be energized if it is not in the Cooling or Free
Cooling mode and the OAT is below 55_F and the SAT is
below 40_F. It will deenergize when the SAT > (SPT +
10_F).
Indoor Air Quality — If the optional indoor air quality
(IAQI) sensor is installed, the PremierLink controller will
maintain indoor air quality within the space at the user
configured differential setpoint (IAQD) in the CONFIG
configuration table. The setpoint is the difference between
the IAQI and an optional outdoor air quality sensor
(OAQ). If the OAQ is not present then a fixed value of
400 ppm is used. The actual space IAQ setpoint (IAQS) is
calculated as follows:
IAQS = IAQD + OAQ (OAQ = 400 ppm if not present)
As air quality within the space changes, the minimum
position of the economizer damper will be changed also
thus allowing more or less outdoor air into the space
depending on the relationship of the IAQI to the IAQS.
The IAQ algorithm runs every 30 seconds and calculates
IAQ minimum position value using a PID loop on the
IAQI deviation from the IAQS. The IAQ minimum
position is then compared against the user configured
minimum position (MDP) and the greatest value becomes
the final minimum damper position (IQMP). If the
calculated IAQ minimum position is greater than the IAQ
maximum damper position (IAQMAXP) decision in the
SERVICE configuration table, then it will be clamped to
IAQMAXP value.
If IAQ is configured for low priority, the positioning of
the economizer damper can be overridden by comfort
requirements. If the SPT > OCSP + 2.5 or the SPT <
OHSP -- 2.5 then IAQ minimum position becomes 0 and
the IQMP = MDP. The IAQ mode will resume when the
SPT ≤ OCSP + 1.0 and SPT ≥ OHSP -- 1.0.
If IAQ is configured for high priority and the OAT < 55_F
and the SAT < (SPT -- 10_F), the algorithm will enable the
heat stages to maintain the SAT between the SPT and the
SPT + 10_F.
If AUXOUT is configured for Reversing Valve Cool, then
the H3_EX_RV contact will be deenergized when there is
a demand for heating. The heat stages will be cycled to
temper the SAT so that it will be between the SPT and the
SPT + 10_F (SPT < SAT < (SPT + 10_F)) if:
S the number of heat stages calculated is zero
S the OAT < 55_F
IAQ Pre--Occupancy Purge — This function is designed to
purge the space of airborne contaminants that may have
accumulated 2 hours prior to the beginning of the next
occupied period. The maximum damper position that will
be used is temperature compensated for cold whether
conditions and can be pre--empted by Temperature
Compensated Start function. For pre--occupancy to occur,
the following conditions must be met:
S IAQ Pre--Occupancy Purge option is enabled in the
CONFIG configuration table
S Unit is in the unoccupied state
S Current Time is valid
76
S Next Occupied Time is valid
S Time is within 2 hours of next Occupied period
S Time is within Purge Duration (user--defined 5 to 60
minutes in the CONFIG configuration table)
S OAT Reading is available
If all of the above conditions are met, the economizer
damperIQMPistemporarilyoverriddenbythe
pre--occupancydamperposition(PURGEMP).The
PURGEMP will be set to one of the following conditions
basedonatmosphericconditionsandthespace
temperature:
S If the OAT ≥ NTLO (Unoccupied OAT Lockout
Temperature) and OAT < 65_F and OAT is less than or
equal to OCSP and Enthalpy = Low then PURGEMP =
100%.
S If the OAT < NTLO then PURGEMP = LTMP (Low
Temperature Minimum Position -- defaults to 10%)
S If the OAT > 65_For(OAT≥ NTLO and OAT > OCSP)
or Enthalpy = High then PURGEMP = HTMP (High
Temperature Minimum Position defaults to 35%).
The LTMP and HTMP are user adjustable values from 0
to 100% in the SETPOINT table. Whenever PURGEMP
results in anumber greater than0%,the IAQ
pre--occupancy purge mode will be enabled turning on the
Indoor Fan Relay and setting the economizer IQMP to the
PURGEMP value. When IAQ pre--occupancy mode is not
active PURGEMP = 0%.
Unoccupied Free Cooling — Unoccupied free cool
function will start the indoor fan during unoccupied times
in order to cool the space with outside air. This function is
performed to delay the need for mechanical cooling when
the system enters the occupied period. Depending on how
Unoccupied Free Cooling is configured, unoccupied mode
can occur at any time in the unoccupied time period or 2
to 6 hours prior to the next occupied time. Once the space
has been sufficiently cooled during this cycle, the fan will
be stopped. In order to perform unoccupied free cooling
all of the following conditions must be met:
S NTEN option is enabled in the CONFIG configuration
table
S Unit is in unoccupied state
S Current time of day is valid
S Temperature Compensated Start mode is not active
S COOL mode is not active
S HEAT mode is not active
S SPT reading is available
S OAT reading is available
S Enthalpy is low
S OAT > NTLO (with 1_F hysteresis) and < Max Free Cool
setpoint
If any of the above conditions are not met, Unoccupied
Free Cool mode will be stopped, otherwise, the mode will
be controlled as follows:
The NTFC setpoint (NTSP) is determined as NTSP =
(OCSP + OHSP) / 2
The Unoccupied Free Cool mode will be started when:
SPT > (NTSP + 2_F) and SPT > (OAT + 8_F)
The Unoccupied Free Cool mode will be stopped when:
SPT < NTSP or SPT < (OAT + 3_F)
Temperature Compensated Start — This function will run
when the controller is in unoccupied state and will
calculate early start bias time (SBT) based on space
temperature deviation from occupied setpoints in minutes
per degree. The following conditions will be met for the
function to run:
S Unit is in unoccupied state
S Next occupied time is valid
S Current time of day is valid
S Valid space temperature reading is available (from sensor
or linkage thermostat)
S Cool Start Bias (KCOOL) and Heat Bias Start (KHEAT)
> 0 in the CONFIG configuration table
The SBT is calculated by one of the following formulas
depending on temperature demand:
If SPT > OCSP then SBT = (SPT -- OCSP) * KCOOL
If SPT < OHSP then SPT = (OHSP -- SPT) * KHEAT.
The calculated start bias time can range from 0 to 255
minutes. When SBT is greater than 0 the function will
subtract the SBT from the next occupied time to calculate
a new start time. When a new start time is reached, the
Temperature Compensated Start mode is started. This
mode energizes the fan and the unit will operate as though
itisinoccupiedstate.Onceset,Temperature
Compensated Start mode will stay on until the unit returns
to occupied state. If either Unoccupied Free Cool or IAQ
Pre--Occupancymodeis active whenTemperature
Compensated Start begins, their mode will end.
Door Switch — The Door Switch function is designed to
disable mechanical heating and cooling outputs when the
REMOCC contact input is closed (in the ON state) after a
programmed time delay. The fan will continue to operate
based on the current mode and the ASHRAE 90.1 Supply
Fan setting. The delay is programmable from 2 to 20
minutes by setting the Remote Cont/Door Switch decision
in the SERVICE table to a value equal to the number of
minutes desired. When the contact is open (in the OFF
state), the PremierLink controller will resume normal
temperature control.
This application is designed for use in schools or other
public places where a door switch can be installed to
monitor the opening of a door for an extended period of
time. The controller will disable mechanical cooling and
heating when the door is open for a programmed amount
of time.
This function can also be used to monitor a high
condensate level switch when installed on a water source
heat pump to disable mechanic cooling in case of a
plugged evaporator condensate pan drain.
Linkage — The Linkage function in the PremierLink
controller is available for applications using a Linkage
thermostat or the 3V control system. If using the Linkage
thermostat, both the PremierLink controller and the stat
must be on the same CCN bus. When used as the air
48TC
77
source for a 3V control system, the PremierLink controller
is not required to be on the same CCN bus but it is
recommended. Linkage will be active when it is initiated
from the Linkage thermostat or the 3V Linkage
Coordinator through CCN communications and requires
no configuration. Only one device can be linked to the
PremierLink controller.
Once Linkage is active, the PremierLink controller’s own
SPT, temperature setpoints, and occupancy are ignored
and the controller will use the information provided by the
remote linkage device. The following information will be
received from the remote linked device and can be viewed
in the maintenance display table:
S Supervisory Element
S Supervisory Bus
S Supervisory Block
48TC
S Average Occupied Heat Setpoint
S Average Occupied Cool Setpoint
S Average Unoccupied Heat Setpoint
S Average Unoccupied Cool Setpoint
S Average Zone Temp
S Average Occupied Zone Temp
S Occupancy Status
In return, the PremierLink controller will provide its SAT
and operating mode to the linked device.
It will convert its operating modes to Linkage modes. See
Table 30.
Table 30 – Linkage Modes
ROOFTOP MODEVALUELINKAGE MODE
Demand LimitN/AN/A
Heat3Heating
Cool or Free Cooling4Cooling
IAQ ControlN/AN/A
Temp. Co mpen s ate d
Start Heat
Temp. Co mpen s ate d
Start Cool
IAQ Purge6Pressurization
Occupied
(Indoor Fan ON)
Unoccupied Free
Cool
Fire Shutdown7Evac
Factory/Field Test1Off
Off1Off
2Warm ---up
4Cooling
4Cooling
5
Unoccupied Free
Cooling
The PremierLink controller will generate a Linkage
Communication Failure alarm if a failure occurs for 5
consecutive minutes once a Linkage has previously been
established. It will then revert back to its own SPT,
setpoints and occupancy schedule for control. For this
reason, Carrier strongly recommends that an SPT be
installed in the space on open plenum systems or in the
return air duct of ducted return air systems to provide
continuedbackupoperation.WhenLinkage
communication is restored, the controller will generate a
return to normal.
For more information on how the PremierLink controller
is used in conjunction with the Carrier 3V control system,
contact your CCN controls representative.
IMPORTANT: The PremierLink controller should not be
used as a linked air source in a ComfortIDt VAV system.
The ComfortID VAV system will NOT function correctly
when applied with a PremierLink controller as the air
source, resulting in poor comfort control and possible
equipment malfunction.
NOTE: The PremierLink controller can be used as an air
source in a 3V Pressure Independent (PI) System (a 3V
LinkageCoordinatorwithComfortIDPIZone
Controllers), but it should not be used as an air source
with ComfortID controllers unless a 3V zone controller is
used as the Linkage Coordinator. Contact your Carrier
CCN controls representative for assistance.
Demand Limit — If the demand limit option is enabled,
the control will receive and accept Redline Alert and
Loadshed commands from the CCN loadshed controller.
When a redline alert is received, the control will set the
maximum stage of capacity equal to the stage of capacity
that the unit is operating at when the redline alert was
initiated.
When loadshed command is received the control will
reduce capacity as shown in Table 31.
Table 31 – Loadshed Command — Gas and Electric
Heat Units
CURRENT CAPACITYNEW CAPACITY
CMP1DX Cooling OFF
CMP1+CMP2CMP1
HS1Heat OFF
HS1+HS2 (+HS3)HS1
The controller will have a maximum demand limit timer
of 1 hour that prevents the unit from staying in load shed
or redline alert longer than 1 hour in the event the
controller loses communication with the network load
shed module. Should the maximum demand limit timer
expire prior to receiving the loadshed device command
from CCN, the control will stop demand limit mode and
return to normal operation.
RTU-- MP Sequence of Operation
The RTU--MP will control the compressor, economizer
and heating outputs based on its own space temperature
input and setpoints. An optional CO
in the space can influence the economizer minimum
position. The RTU--MP has its own hardware clock that is
set automatically when the software is installed on the
board. The RTU--MP’s default is to control to occupied
setpoints all the time, until a type of occupancy control is
set. Occupancy types are described in the scheduling
section. The following sections describe the operation for
the functions of the RTU--MP. All point objects that are
referred to in this sequence will be in reference to the
objects as viewed in BACview
Scheduling
Scheduling is used to start heating or cooling (become
occupied) based upon a day of week and a time period and
78
IAQ sensor mounted
2
6
Handheld.
control to the occupied heating or cooling setpoints.
Schedulingfunctions arelocatedunder occupancy
determination and the schedule menu accessed by the
Menu softkey (see Appendix -- for menu structure). Your
local time and date should be set for these functions to
operate properly. Five scheduling functions are available
by changing the Occupancy Source to one of the
following selections:
Always Occupied (Default Occupancy)
The unit will run continuously. RTU--MP ships from the
factory with this setting.
Local Schedule
The unit will operate according to the schedule configured
and stored in the unit. The local schedule is made up of
three hierarchy levels that consist of two Override
schedules, twelve Holiday and four Daily schedules, and
are only accessible by the BACview screen (handheld or
virtual).
The Daily schedule is the lowest schedule in the hierarchy
and is overridden by both the Holiday and Override
schedule. It consists of a start time, a stop time (both in 24
hour mode) and the seven days of the week, starting with
Monday and ending in Sunday. To select a daily schedule
scroll to the Schedules menu off of the Menu selection.
Enter the User password and change the Occupancy
Source to Local Schedule. Scroll down and over to the
Daily menu and press enter. Choose one of the four Daily
schedules by pressing the Next softkey and change the
Use? point from NO to YES by selecting the point and
pressing the INCR or DECR softkey. Press the OK softkey
and scroll to the start and stop times. Edit these times
following the same steps as the Use? point. Finally scroll
down to the Days: section and highlight the days required
for the Daily schedule by INCR or DECR softkeys and
press OK softkey.
The Holiday schedule is created to override the Daily
schedule and identify a specific day and month of the year
to start and stop the unit and change control to the
unoccupied heating and cooling setpoints. Follow the
same steps to turn on one of the twelve Holiday schedules
and start and stop times. Next, select one out of the twelve
months and one out of the thirty--one days of that month.
The RTU--MP will now ignore the Daily schedule for the
specific day and time you selected and follow the Holiday
Schedule for this period.
The Override schedules primary purpose is to provide a
temporary change in the occupied heating and cooling
setpoints and force the unit to control to the unoccupied
heating and cooling setpoints. This would occur on a set
day in a particular month and last during the start and stop
time configured. The Override schedule is enabled by
following the same steps to create the Holiday schedule.
NOTE:Push button override is only available when
running a local or BACnet Schedule.
BACnet Schedule
For use with a Building Automation System that supports
native BACnet scheduling is scheduling the unit. With the
Occupancy Source set to BACnet schedule the BAS will
control the unit through network communication and it’s
own scheduling function.
BAS On/Off
The Building Automation System is scheduling the unit
via an On/Off command to the BAS ON/OFF software
point. The Building Automation System can be speaking
BACnet, Modbus, or N2 and is writing to the BAS On/Off
point in the open protocol point map.
NOTE:If theBAS supports NATIVE BACnet
scheduling, then set the Occupancy Source to BACnet
schedule. If the BAS is BACnet but does NOT support
NATIVE BACnet scheduling, then set the Occupancy
Source to BAS On/Off.
DI On/Off
A hard--wired input on the RTU--MP will command the
unit to start/stop. Inputs 3, 5, 8, and 9 on plug J5 can be
hard--wired to command the unit to start/stop.
NOTE: Scheduling can either be controlled via the unit
or the BAS, but NOT both.
Indoor
Fan
The indoor fan will be turned on whenever any one of the
following conditions is true:
S It is in the occupied mode. This will be determined by its
own internal occupancy schedule.
S Whenever there is a demand for cooling or heating in the
unoccupied mode.
S Whenever the remote occupancy switch is closed during
DI On/Off schedule type or if occupancy is forced
occupied by the BAS during BAS On/Off schedule type.
When transitioning from unoccupied to occupied, there
will be a configured time delay of 5 to 600 seconds before
starting the fan. The fan will continue to run as long as
compressors, heating stages, or the dehumidification
relays are on when transitioning from occupied to
unoccupied with the exception of Shutdown mode. If Fire
Shutdown, safety chain, SAT alarm or SPT alarm are
active; the fan will be shutdown immediately regardless of
the occupancy state or demand.
The RTU--MP has an optional Supply Fan Status input to
provide proof of airflow. If this is enabled, the point will
look for a contact closure whenever the Supply Fan Relay
is on. If it is not enabled then it will always be the same
state as the Supply Fan Relay. The cooling, economizer,
heating, dehumidification, CO
and power exhaust
2
routines will use this input point for fan status.
Cooling
The compressor outputs are controlled by the Cooling
Control PID Loop and Cooling Stages Capacity algorithm.
They will be used to calculate the desired number of
stages needed to satisfy the space by comparing the Space
Temperature (SPT) to the Occupied Cool Setpoint plus the
T56 slider offset when occupied and the Unoccupied Cool
Setpoint (UCSP) plus the T56 slider offset, if unoccupied.
The economizer, if available, will be used for cooling in
addition to the compressors. The following conditions
must be true in order for this algorithm to run:
S Indoor Fan has been ON for at least 30 seconds.
S Heat mode is not active and the time guard between
modes equals zero.
S If occupied and the SPT >(occupied cool setpoint plus
48TC
79
the T56 slider offset).
S Space Temperature reading is available.
S If it is unoccupied and the SPT > (unoccupied cool
setpoint plus the T56 slider offset). The indoor fan will be
turned on by the staging algorithm.
S If economizer is available and active and economizer
open > 85% and SAT > (SAT low limit + 5_F) and SPT >
effective setpoint + 0.5_F.
OR
Economizer is available, but not active
OR
Economizer is not available
S OAT > DX Lockout temperature.
If all of the above conditions are met, the compressors
will be energized as required, otherwise they will be
de--energized.
There is a fixed 3--minute minimum on time and a
48TC
5--minute off time for each compressor output and a
3--minute minimum time delay between staging up or
down.
Any time the compressors are running the RTU--MP will
stage down the compressors if the SAT becomes less than
the cooling low supply air setpoint.
After a compressor is staged off, it may be started again
after a normal time--guard period and the supply air
temperature has increased above the low supply air
setpoint.
Economizer
The Economizer dampers are used to provide free cooling
and Indoor Air Quality, if optional CO
sensor is installed,
2
when the outside conditions are suitable.
The following conditions must be true for economizer
operation:
S Indoor Fan has been on for at least 30 seconds.
S Enthalpy is Low if the Enthalpy input is enabled.
S SAT reading is available.
S OAT reading is available.
S SPT reading is available.
S OAT <= High OAT economizer lockout configuration
(default = 75).
S OAT <= SPT
If any of the mentioned conditions are not true, the
economizer will be set to its configured minimum
position.Theminimumdamperpositioncanbe
overridden by the IAQ routine described later in this
section.
If the above conditions are true, the Economizer Control
Master Loop will calculate a damper position value based
on the following calculation:
Damper Position = minimum position + PID (SPT -- econ
setpoint). Econ setpoint is half way between the effective
cool and heat setpoints. If the SAT drops below the
cooling low supply air setpoint (+ 5_F), the economizer
will ramp down to minimum position.
Exhaust
Power
If RTU--MP is also controlling an exhaust fan, it can be
enabled based on damper position or by occupancy. If
configured for continuous occupied operation, it will be
energized whenever the controller is in the occupied mode
and disabled when in the unoccupied mode. If configured
for damper position control, it will be energized whenever
the economizer exceeds the power exhaust setpoint and
disabled when the economizer drops below the setpoint by
a fixed hysteresis of 10%.
Heating
The heating outputs are controlled by the Heating Control
PID Loop and Heating Stages Capacity algorithm. They
will be used to calculate the desired number of stages
needed to satisfy the space by comparing the SPT to the
Occupied Heat Setpoint plus the T56 slider offset when
occupied and the Unoccupied Heat Setpoint plus the T56
slider offset if unoccupied. The following conditions must
be true in order for this algorithm to run:
S Indoor Fan has been ON for at least 30 seconds.
S Cool mode is not active and the time guard between
modes equals zero.
S If occupied and SPT <(occupied heat setpoint plus T56
slider offset)
S SPT reading is available
S If it is unoccupied and the SPT < (unoccupied heat
setpoint plus T56 slider offset). The indoor fan will be
turned on by the staging algorithm.
S OAT < High OAT lockout temperature.
If all of the above conditions are met, the heating outputs
will be energized as required, otherwise they will be
de--energized. If the SAT begins to exceed the high supply
air setpoint, a ramping function will cause the Heat Stages
Capacity algorithm to decrease the number of stages until
the SAT has dropped below the setpoint.
There is a fixed one minute minimum on time and a one
minute off time for each heat output. Heat staging has a 3
minute stage up and 30 second stage down delay.
Indoor Air
Quality
If the optional indoor air quality sensor is installed, the
RTU--MP will maintain indoor air quality within the space
at the user configured differential setpoint. The setpoint is
the difference between the indoor air quality and an
optional outdoor air quality sensor. If the outdoor air
quality is not present then a fixed value of 400ppm is
used. The following conditions must be true in order for
this algorithm to run:
S The mode is occupied.
S Indoor Fan has been ON for at least 30 seconds.
S Indoor Air Quality sensor has a valid reading
As air quality within the space changes, the minimum
position of the economizer damper will be changed thus
allowing more or less outdoor air into the space depending
on the relationship of the indoor air quality to the
differential setpoint. If all the above conditions are true,
the IAQ algorithm will run and calculates an IAQ
minimum position value using a PID loop. The IAQ
minimum damper position is then compared against the
user configured economizer minimum position and the
greatest value becomes the final minimum damper
position of the economizer output.
80
If the calculated IAQ minimum position is greater than
the IAQ maximum damper position configuration then it
will be clamped to the configured value.
Demand
Limit
If the RTU--MP receives a level 1 (one degree offset), 2
(two degree offset), or a 3 (4 degree offset) to the BACnet
demand limit variable, the controller will expand the
heating and cooling setpoints by the configured demand
limit setpoint value and remain in effect until the BACnet
demand limit variable receives a 0 value.
FASTENER TORQUE VALUES
See Table 32 for torque values.
Table 32 – Torque Values
Supply fan motor mounting1 2 0 +/ --- 12 i n --- l b s
Supply fan motor adjustment plate1 2 0 +/ --- 12 i n --- l b s
Motor pulley setscrew72+/ --- 5 in ---lbs
Fan pulley setscrew72+/ --- 5 in ---lbs
Blower wheel hub setscrew72+/--- 5 in --- lbs
Bearing locking collar setscrew6 5 --- 70 i n --- lb s
Compressor mounting bolts65 --- 7 5 in --- l b s
Condenser fan motor mounting bolts2 0 + / --- 2 in --- l b s
Condenser fan hub setscrew8 4 + / --- 1 2 i n --- l b s
48TC
81
Model Number Nomenclature
Unit Heat Type
48 = Gas heat pkg rooftopBrand / Packaging
Tier / Model1=LTL
TC = Entry tier (with Puron refrigerant)
Heat SizeC = N on --- f u s e d d isc
D=LowheatD=Thruthebase
E = Medium heatF = Non---fused & thru the base
F=Highheat
L=LowNOx,lowheatService Options
48TC
M=LowNOx, medium heat0=None
N=LowNOx,highheat1 = Unpowered convenience outlet
S = Stainless steel, low heat2 = Powered convenience outlet
R = Stainless steel, medium heat
T = Stainless steel, high heat
Refrig. System OptionsB=Tempeconow/barorelief
A = Standard refrigeration systemF = Enthalpy econo w/ baro relief
A=NoneVoltage
B = RA smoke detector1 = 575/3/60
C = SA smoke detector3 = 208 --- 230/1/60
D=RA&SAsmokedetector5 = 208 --- 230/3/60
E=CO2sensor
F = RA smoke detector & CO
G = SA smoke detector & CO
H=RA&SAsmokedetector&CO
Indoor Fan OptionsD=EcoatAl/Cu --- EcoatAl/Cu
1 = Standard static optionE = Cu/Cu --- Al/Cu
2 = Medium static optionF = Cu/Cu --- Cu/Cu
3 = High static optionM = A l / C u --- A l / C u --- L o u v e r e d H a il G u a r d s
1
1
Future availability
1
2
1
2
1
2
6 = 460/3/60
Coil Options (Outdoor Coil --- Indoor Coil)
A = Al/Cu --- Al/Cu
B = P r e coat A l / C u --- A l / C u
C = E coat A l / C u --- A l / C u
N = P r e coat A l / C u --- A l / C u --- L o u v e r e d Hail G u a r d s
P = E co a t A l / C u --- A l / C u --- L o u v e r e d Hail G u a r d s
Q = E coat A l / C u --- E c o a t A l / C u --- L o u v e r e d Ha i l G u ard s
R = C u /C u --- Al / C u --- L o u vered H a i l G u a r d s
S = C u / Cu --- C u/C u --- Louve r e d H a i l G u a r ds
Serial Number Format
POSITION NUMBER12345678910
TYPICAL1208G12346
POSITIONDESIGNATES
1---2Week of manufacture (fiscal calendar
3---4Year of manufacture (“08” = 2008)
1. Interpolation is permissible. Do not extrapolate.
2. External static pressure is the static pressure difference between the return duct and the supply duct plus the static
pressure caused by any FIOPs or accessories.
3. Tabular data accounts for pressure loss due to clean filters, unit casing, and wet coils. Factory options and accessories
may add static pressure losses.
4. The Fan Performance tables offer motor/drive recommendations. In cases when two motor/drive combinations would
work, Carrier recommended the lower horsepower option.
5. For information on the electrical properties of Carrier’s motors, please see the Electrical information section of this
book.
48TC
87
APPENDIX III. FAN PERFORMANCE (cont.)
48TC**041 Phase3 Ton Horizontal Supply
AVAILABLEEXTERNALSTATICPRESSURE(in.wg)
0.20.40.60.81.0
RPMBHPRPMBHPRPMBHPRPMBHPRPMBHP
1.21.41.61.82.0
RPMBHPRPMBHPRPMBHPRPMBHPRPMBHP
1
Medium Static OptionF i e l d --- S u p p l i e d D r i ve