Bryant 548J User Manual

548J

SINGLE PACKAGE HEAT PUMP/ELECTRIC HEAT NOMINAL 3 TO 8.5 TONS WITH PURON

(R--410A) REFRIGERANT

Service and Maintenance Instructions

TABLE OF CONTENTS

SAFETY CONSIDERATIONS 1....................

UNIT ARRANGEMENT AND ACCESS 3...........

SUPPLY FAN (BLOWER) SECTION 4..............

HEAT PUMP REFRIGERATION SYSTEM 8.........

PURON

COOLING CHARGING CHARTS 14................

CONVENIENCE OUTLETS 19....................

HEAT PUMP CONTROLS 20......................

PROTECTIVE CONTROLS 20.....................

COMMERCIAL DEFROST CONTROL 21...........

ELECTRIC HEATERS 24.........................

SMOKE DETECTORS 26.........................

RTU--MP CONTROL SYSTEM 33..................

ECONOMIZER SYSTEMS 47.....................

WIRING DIAGRAMS 56.........................

PRE--START-UP 58..............................

START-UP, GENERAL 58.........................

START-UP, RTU--MP CONTROL 59................

OPERATING SEQUENCE 62......................

FASTENER TORQUE VALUES 67.................

APPENDIX I. MODEL NUMBER SIGNIFICANCE 68...

APPENDIX II. PHYSICAL DATA 69................

APPENDIX III. FAN PERFORMANCE 71...........

(R--410A) REFRIGERANT 13.............

SAFETY CONSIDERATIONS

Installation and servicing of air-conditioning equipment can be hazardous due to system pressure and electrical components. Only trained and qualifi ed service personnel should install, repair, or service air-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. Have fire extinguishers available for all brazing operations.

Follow all safety codes. Wear safety glasses and work gloves. Use quenching cloth for brazing operations. Have fire extinguisher 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

APPENDIX IV. ELECTRICAL INFORMATION 82....

APPENDIX V. WIRING DIAGRAM LIST 96.........

APPENDIX VI. MOTORMASTER SENSOR

LOCATIONS 97.................................

UNIT START-UP CHECKLIST 99..................

WARNING

548J

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 out let 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.

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 system s. Do not use R--22 service equipment or components on Puron refrigerant equipment.

PERSONAL INJURY AND ENVIRONMENTAL HAZARD

Failure to follow this warning could cause personal injury or death. Relieve pressure and recover all refrigerant before system repair or final unit disposal. Wear safety glasses and gloves when handling refrigerants. Keep torches and other ignition sources away from refrigerants and oils.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and wear appropriate protective clothing, safety glasses and gloves when handling parts and servicing air conditioning units.

UNIT ARRANGEMENT AND ACCESS

Seasonal Maintenance

General

Fig. 1 and Fig. 2 show general unit arrangement and access locations.

CONTROL BOX

INDOOR BLOWER ACCESS

COMPRESSORS (D08-09 only)

C09190

Fig. 1 -- Typical Access Panel Location (Front)

FILTER ACCESS PANEL

These items should be checked at the beginning of each season (or more often if local conditions and usage patterns dictate):

Air Conditioning/Heat

Pump

S Outdoor fan motor mounting bolts tightness S Compressor mounting bolts S Outdoor fan blade positioning S Control box cleanliness and wiring condition S Wire terminal tightness S Refrigerant charge level S Indoor coil cleaning S Supply blower motor amperage

Electric

Heating

S Power wire connections S Fuses ready S Manual--reset limit switch is closed

Economizer or Outside Air

Damper

S Inlet filters condition S Check damper travel (economizer) S Check gear and dampers for debris and dirt

Air Filters and Scr

eens

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INDOOR COIL ACCESS PANEL

C08449

Fig. 2 -- Typical Access Panel Locations (Rear)

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:

Quarterly Inspection (and 30 days after initial start

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 chec ked S Outdoor coil cleanliness checked S Condensate drain checked

)

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.)

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: DO NOT OPERATE THE UNIT WITHOUT THESE FILTERS!

Outside Air Hood

Outside air hood inlet screens are permanent 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.)

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BAROMETRIC RELIEF

DIVIDER

CLEANABLE ALUMINUM FILTER

OUTSIDE AIR

FILTER

HOOD

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.

FILTER CLIP

C08634

SUPPLY FAN (BLOWER) SECTION

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could cause persona l 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 (Direct--Drive)

For unit sizes 04, 05 and 06, the Standard Static supply fan system consists of a direct--drive forward--curved centrifugal blower wheel attached to the motor shaft. The motor has taps to provide the servicer with the selection of one of five motor torque/speed ranges to best match wheel performance with attached duct system. See Fig. 5 (548J Direct--Drive Fan Assembly) and Fig. 6 (EMC Motor Connectors).

EMC Motor

95°

Motor Plug Position

(95° from vertical)

EMC Power Transformer (460, 575v)

Manual Outside Air Hood Screen

This inlet screen is secured by a retainer angle across the top edge of the hood. (See Fig. 4.)

C07156

Fig. 4 -- Screens Installed on Outdoor--Air Hood

(Sizes 08D--09D Shown)

To remove the screen, loosen the screws in the top retainer 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.

Fig. 5 -- 548J Direct--Drive Supply Fan Assembly

YEL

Gnd

GRN/YEL

BLU

LGN

Com BRN

Speed

Taps

12345

VIO Default Connection

Fig. 6 -- EMC Motor Connectors

C09260

Motor Power Connections

C09261

460, 575-v Units

208/230-v Units

Fig. 7 -- EMC Unit Wiring

548J

C09263

ECM Motor – The direct--drive motor is an X13 Electronically Commutated motor (ECM). An ECM contains electronic circuitry to convert single--phase line AC voltage into a 3--phase DC voltage to power the motor circuit. The motor circuit is a DC brushless design with a permanent magnet rotor. On the X13 design, the electronic circuitry is integral to the motor assembly and cannot be serviced or replaced separately.

208/230--v units use a 230--v motor. 460--v units use a 230--v motor with a stepdown transformer (mounted on the end of the fan housing, see Fig. 5). 575--v units use a 460--v motor with an autotransformer. Motor power voltage is connected to motor terminals L and N (see Fig. 6 and Fig. 7); ground is connected at te rminal G. The motor power voltage is ALWAYS present; it is not switched off by a motor contactor.

Motor operation is initiated by the presence of a 24-- v control signal to one of the fi ve motor communications terminals. When the 24--v signal is removed, the motor will stop. The motor control signal is switched by the defrost board’s IFO output.

Evaluating motor speed – The X13 ECM is a constant torque motor design. The motor speed is adjusted by the motor control circuitry to maintain the programmed shaft torque. Consequently there is no specific speed value assigned to each control tap setting. At the Position 5 tap, the motor speed is approximately 1050 RPM (17.5 r/s) but it will vary depending on fan wheel loading.

Selecting speed tap – The five communications terminals are each programmed to provide a different motor torque output. See Table 1. Factory default tap selection is Position 1 for lowest torque/speed operation.

Table 1 – 548J Standard Static Motor Tap Programing

(percent of full--load torque)

Unit Size Ta p 1 Tap 2 Ta p 3 Ta p 4 Tap 5

04 32 38 45 50 100 05 46 58 61 69 100 06 73 82 85 90 100

Factory Default: Tap 1 (VIO)

To select another speed:

1. Disconnect main power to the unit.

2. Remove the motor signal lead (VIO) a t the motor communications terminal.

3. Reconnect the motor signal lead to the desired speed terminal.

4. Connect main power to the unit.

Motor “rocking” on start--up – When the motor first starts, the rotor (and attached wheel) will “rock” back and forth as the motor tests for rotational direction. Once the correct rotation direction is determined by the motor circuitry, the motor will ramp up to specified speed. The “rocking” is a normal operating characteristic of ECM motors.

Troubleshooting the ECM motor – Troubleshooting the X13 ECM requires a voltmeter.

1. Disconnect main power to the unit.

2. Remove the motor power plug (including the control BRN lead) and VIO control signal lead at the motor terminals.

3. Restore main unit power.

4. Check for proper line vol tage at motor power leads BLK (from L terminal) and YEL (from N terminal).

Table 2 – Motor Test Volts

Unit Voltage Motor Voltage Min ---Max Volts

208/230 230 190---250

460 230 210---250 575 460 420---500

5. Apply a jumper at uni t control terminals R to G to initiate a demand for motor operation. Check for 24--v output at defrost board terminal IFO.

6. Check for proper control signal voltage at motor signal leads VIO and BRN. Signal should be 22 to 28--v.

7. Disconnect unit main power.

8. Reconnect motor power and control signal leads at the motor terminals.

9. Restore unit main power.

Motor should start and run. If it does not, remove the

548J

motor assembly. Replace with same motor part number; do not substitute with an alternate design as torque/speed programming will not be same as on original factory motor.

Replacing the ECM Motor – Before removing the ECM belly--band mounting ring, measure the distance between the base of the motor shaft and the edge of the mounting ring. Remove the motor mounting band and transfer to the replacement motor. Position the mounting band at distance measured in first step. Snug the mounting bolt but do not tighten yet.

Insert the motor shaft into the fan wheel hub. Then secure the three motor mount arms to the support cushions. Torque the arm mounting screws to 60 in--lbs (6.8 N--m).

Center the fan wheel in the fan housing. Torque the fan wheel hub setscrew to 120 in -- lbs (13.6 N--m).

Ensure the motor terminals are located at a position below the 3 o’clock position (see Fig. 5). Tighten the motor belly--band bolt to 80 in--lbs (9.0 N--m).

Supply Fan (Belt--Drive)

The belt--drive 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. 8.)

C07087

Fig. 8 -- Belt Drive Motor Mounting

Belt

Check the belt condition and tension quarterly. Inspect the belt for signs of cracking, fraying or glazing along the 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

/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

/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 be lt 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 gentl y 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 Motor

The motor pull ey 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 fixe d flange side that increases or reduces the pitch diameter of this driver pulley. (See Fig. 9.)

4. Recheck belt tension.

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. 10.

548J

C07075

Fig. 9 -- Supply--Fan Pulley Adjustment

As the pitch diameter is c hanged by adjusting the position of the movable flange, the centerline on this pul ley shifts laterally (along the motor shaft). This creates a requirement for a realignment of the pulleys aft er 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 e rosion on these surfaces are signs of improper belt tension and/or belt slippage. Pulley replacement may be necessary.

To change fan speed:

1. Shut off unit power supply.

2. Loosen belt by loosening fan motor mounting nuts. (See Fig. 8.)

3. Loosen movable pulley flange setscrew. (See Fig. 9.)

4. Screw movable flange toward fixed flange t o 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 fla nge 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.

C08121

Fig. 10 -- Tightening Locking Collar

Motor

When replacing the motor, also re place 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.

To reduce vibration, replace the motor’s adjustable pitch pulley with a fixed pitch pulley (after the final airflow balance adjustment). This will re duce the amount of vibration generated by the motor/belt--drive system.

HEAT PUMP REFRIGERATION

SYSTEM

WARNING

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could cause persona l injury, death and/or equipment damage.

This system uses Puron higher pressures than R--22 and ot her refrigera nts. 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 equipm ent, consult the equipm ent manufacturer.

refrigerant which has

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.

Periodic Clean Water

A periodic clean water rinse is very beneficial for coils that are appli ed in coastal or industrial environments. However, it is very important that the water rinse is made with very low velocity water stream to avoid damaging the fin edges. Monthly cleaning as described below is recommended.

Rinse

CAUTION

Outdoor Coil

548J

The 548J outdoor coil is fabricated with round tube copper hairpins and plate fins of various materials and/or coatings (see “Appendi x I -- Model Number Significance” to identify the materials provided in this unit). All unit sizes use composite--type two--row coils. Composite two--row coils are two single--row coils fabricated with a single return bend end tubesheet.

Indoor Coil

The indoor coil is traditional round--tube, plate --fin technology. Tube and fin construction is of various optional materials and coatings (see Model Number Format). Coils are multiple--row.

Outdoor 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 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

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 the coating of a protected coil) if the tool is applied across the fins.

Fibers

PERSONAL INJURY AND UNIT DAMAGE HAZARD

Failure to follow this caution may result in personal injury or equipment damage.

Only approved cleaning is recommended.

Routine Cleaning of Indoor Coil Surfaces

Periodic cleaning with Totaline coil cleaner is essential to e xtend the life of coils. This cleaner is available from our Replacement Components Division as part number P902--0301 for one gallon container, a nd part number P902--0305 for a 5 gallon container. It is recommended that all coils, including standard aluminum, pre--coated, copper/copper or E--coated coils be cleaned with the Totaline 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 the use of

S coil brighteners S acid cleaning prior to painting S high pressure washers S poor quality water for cleaning

Totaline environmenta lly sound coil cleaner is nonflammable, hypoallergenic, 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.

environmentally sound

Clean coil as follows:

1. Turn off unit power, tag disconnect.

2. Remove top panel screws on outdoor coil end of unit.

3. Remove coil corner post. See Fig. 11. To hold top panel open, place coil corner post between top panel and center post. See Fig. 12.

OUTDOOR COIL

C09219

Fig. 11 -- Cleaning Condenser Coil (Size 04--07 shown)

7. Secure inner a nd 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.

Totaline Environmentally Sound Coil Cleaner Application Equipment

/2gallon garden sprayer

S 2 S Water rinse with low velocity spray nozzle

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in corrosion and damage to the unit.

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 Totali ne environmentally sound coil cleaner as described above.

548J

C08206

Fig. 12 -- Propping Up Top Panel

4. For Sizes 04--07: Remove screws securing coil to compressor plate and compressor access panel.

5. For Sizes 08--09: Remove fastener holding coil sections together at return end of condenser coil. Ca refully separate the outdoor coil section 3 to 4 in. from the inner coil section. See Fig. 13.

OUTDOOR COIL

C09220

Fig. 13 -- Separating Coil Sections

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.

CAUTION

UNIT DAMAGE HAZARD

Failure to follow this caution may result in reduced unit performance.

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.

Totaline Environmentally Sound Coil Cleaner Application Instructions

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 carefull not to bend fins.

4. Mix Totaline environmentally sound coil cleaner in a

/2gallon garden spryer according to the instruc-

2 tions included with the cleaner. The optimum solution temperature is 100°F(38°C).

NOTE: Do NOT USE water in excess of 130°F(54°C), as the 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 e xterior 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. Reapply cleaner as needed to ensure 10--minute saturation is achieved.

11. Thoroghly rinse all surfaces with low velocity clean water using downward rinsing motion of water spray nozzle. Protect fins from damage from the spray nozzle.

Indoor Coil

Cleaning the Indoor Coil

548J

1. Turn unit power off. Install lockout tag. Remove indoor 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.

Filter Drier

LPS/LOC

5. Reinstall economizer and filters.

6. Reconnect wiring.

7. Replace access panels.

Refrigeration System

Components

Each heat pump refrigeration system includes a compressor, accumulator, reversing valve, dual--function outdoor coil with vapor header check valve, cooling liquid line with filter drier and check valve, dual--function indoor coil with vapor header check valve, and heating liquid line with check valve and strainer. Unit sizes 04A--07A have a single compressor--circuit; unit sizes 08D and 09D have two compressor--circuits. See Fig. 14 for typical unit piping schematic (unit size 09D (4--row indoor coil) with two compressor--circuits is depicted).

Dual--function outdoor and indoor coils are designed to provide parallel coil circuits during evaporator--function operation and converging coil circuits during condenser--function operation.

Refrigerant flow metering in the evaporator--function sequence is provided by multiple Acutrols – fixed--bore metering devices that are located in the tee nipples between the liquid header and the entrance to each coil circuit. The Acutrol metering device is swaged into the nipple tube between the liquid header end and the side--port tube. See Fig. 15. During evaporator--function operation, flow is straight through the nipple and into each evaporator circuit. Flow continues through the parallel evaporator circuits and into the vapor heade r.

DFT 2

Acutrol

DFT 1

Outdoor Coil

ACCUMULATOR

Heating Mode Liquid Lines

Cooling Liquid Lines

HPS

COMPRESSOR

Comp 2

ACCUMULATOR

COMPRESSOR

HPS

Comp 1

Indoor Coil

Strainer

Fig. 14 -- Typical Unit Piping Schematic (09D unit with 4--row indoor coil)

Acutrol

C09228

Evaporato Coil Circuits

Metering Orifice

From Liquid Header

C09229

Fig. 15 -- Heat Pump Acutrol — Flow as Evaporator

Function

Converging circuit flow in the condenser--function operation is accomplished with the check valve in the vapor header and the liquid transfer header connected to the side ports on all but one of the Acurator tee nipples in each circuit. During condenser --function operation, hot gas from the compressor discharge enters the header until it reaches the check valve which blocks further flow. The hot gas exits the header through the tubes above the check valve and enters these coil circuits. At the outlet of these desuperheating and condensing circuits, the refrigerant enters the Acurater tees from the coil end. The refrigerant exits the tee at the side port and enters the liquid transfer header (see Fig. 16). The refrigerant moves through the liquid transfer header and exits through the remai ning tubes, through the side ports on the Acutrol tees (see Fig. 17) and back into the coil circuits where additional condensing occurs. These circuits exit into the vapor header behind the check valve and exit through the remaining tube on the vapor header. In this last pass through the coil, the refrigerant is subcooled. Subcooled liquid exits at the last Acutrol tee (see Fig. 18) where the side port is connected to the specific mode liquid line.

From Condenser Coil Circuits

To Condensing Circuit

From Transfer Header

C09231

Fig. 17 -- Heat Pump Acutrol — Flow as Condenser

Function/Entering Second Pass

DFT Location (Outdoor Coils only)

From Subcoole Circuit

To Liquid Line

C09232

Fig. 18 -- Heat Pump Acutrol — Flow as Condenser

Function/ Exiting Subcooler Pass

Each liquid line has a check valve to prevent backflow through the liquid line in its opposite mode. Thi s ensures correct flow direction through filter driers and strainers and prevents emptying of off-- mode liquid lines into evaporator--function coil circuits.

Reversing Valve and Check Valve Position

SeeFig.14onpage10.

Table 3 – Cooling Mode (each circuit)

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To Transfer Header

Fig. 16 -- Heat Pump Acutrol — Flow as Condenser

Function/ Exiting First Pass

C09230

Component Status/Position

Reversing Valve Energized

Check Valve A Closed

Check Valve B Open

Check Valve C Closed

Check Valve D Open

Table 4 – Heating Mode (each circuit)

Component Status/Position

Reversing Valve De--- energized

Check Valve A Open

Check Valve B Closed

Check Valve C Open

Check Valve D Closed

Table 5 – Defrost Mode

04A---07A and 08D---09D/Circuit 2:

Component

Defrost Thermostat Closed

Outdoor Fan(s) Off

Reversing Valve Energized

Check Valve A Closed

Check Valve B Open

Check Valve C Closed

Check Valve D Open

Status/Position

Troubleshooting Refrigerant Pressure Problems and Check Valves

Refer to Fig. 14, on page 10, and t he Cooling Mode and Heating Mode tables (Tables 3 and 4) on page 11.

548J

Coil Metering

The metering devices are multiple fixed–bore devices (Acutrolt) swaged 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.

Check for possible blockage of one or more of these metering devices by creating a low load condition on the evaporator--function coil and then observing the frosting pattern on the finned portion of the coil.

To c heck the indoor coil, disconnect the supply fan signal (04A--06A direct--drive fans) or contactor (IFC) coil, then

Devices

start the circuit in a Cooling Mode (jumper R to Y1 or Y2) and observe the frosting pattern on the face of the indoor coil. A frost pattern should develop uniformly across the face of the indoor coil starting a t each tube at the Acutrol nipple locations.

To check the outdoor coil, disconnect the outdoor fan motor. Start the circuit in a Heating Mode (jumper R to W1 or W2) and observe the frost pattern on the face of the outdoor coil.

Failure to develop frost at an outlet tube can indicate a plugged or a missing orifice.

Refrigerant System Pressure Access Ports

There are two access ports in each circuit -- 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. (See Fig. 19.) This check valve is permanently assembled into this core body a nd 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 re cover the entire system refri gerant charge. Apply compressor refrigerant oil t o the check valve core’s bottom o--ring. Install the fitting body with 96 +/--10 in--lbs of torque; do not overtighten.

5/8” HEX

SEAT

.47

1/2-20 UNF RH

0.596

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. 19 -- CoreMax Access Port Assembly

CORE

(Part No. EC39EZ067)

1/2" HEX

45°

DEPRESSOR PER ARI 720 +.01/-.035 FROM FACE OF BODY

7/16-20 UNF RH

C08453

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 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) whe n removing liquid refrigerant for charging. For a cyli nder 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 t he 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.

To Use Cooling Charging

Charts

Take the outdoor ambient temperature and read t he 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.

SIZE DESIGNATION

04A 3 05A 4 06A 5

07A 6 08D 7.5 09D 8.5

NOMINAL TONS

REFERENCE

EXAMPLE:

Model 548J*04A

Outdoor Temperature 85_F(29_C)..................

Suction Pressure 140 psig (965 kPa).................

Suction Temperature should be 55_F(13_C)..........

Compressors

548J

Refrigerant Charge

Amount of refrigerant charge is listed on the unit’s nameplate. Refer to the GTAC2--5 Charging, Recovery, Recycling and Reclamation training manual and the following procedures.

Unit panels m ust be in place when unit is operating during the charging procedure. If unit is equipped with a head pressure control device, bypass it to ensure full fan operation during charging.

Charge checking and adjustments must be made while the system is operating in Cooling only.

Charge

Use standard evacuation techniques for Puron (R--410A) refrigerant.. After evacuating system, weigh in the specified amount of refrigerant.

Low--Charge

Using Cooli ng Charging Charts, Fig. 20 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 tempera ture 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--a ir cfm must be within the normal operating range of the unit.

Cooling

Lubrication

Compressors are 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.

Replacing Compressor

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 in--lbs (7.3--8.5 Nm).

548J

COOLING CHARGING CHARTS

Fig. 20 -- Cooling Charging Charts-- 548J*04A

C09184

Fig. 20 (cont.) -- Cooling Charging Charts -- 548J*05A

C09185

Fig. 20 (cont.) -- Cooling Charging Charts -- 548J*06A

548J

C09186

Fig. 20 (cont.) -- Cooling Charging Charts -- 548J*07A

C09187

548J

C09188

Fig. 20 (cont.) -- Cooling Charging Charts -- 548J*08D

Fig. 20 (cont.) -- Cooling Charging Charts -- 548J*09D

C09189

Compressor Rotation

Filter Drier

CAUTION

PERSONAL INJURY HAZARD

Failure to follow this caution may result in personal injury.

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 doe s 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.

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.

Outdoor Fan Location

See Fig. 21.

1. Shut off unit power supply. Install lockout tag.

2. Remove condenser --fan assembly (grille, motor, and fan).

3. Loosen fan hub setscrews.

4. Adjust fan height as shown in Fig. 21.

5. Tighten setscrews to 84 in--lbs (9.5 Nm).

6. Replace condenser--fan assembly.

Conduit

0.14 in + 0.0 / -0.03

C08448

Fig. 21 -- Outdoor Fan Adjustment

Troubleshooting Cooling System

Refer to Table 6 for additional troubleshooting topics.

548J

PROBLEM CAUSE REMEDY

Compressor an d Outdoor Fan Will Not Start.

Compressor Will Not Start But Outdoor Fan Runs.

548J

Compressor Cycles (Other Than Normally Satisfying Thermostat).

Compressor Operates Continuously.

Compressor Makes Excessive Noise.

Excessive Head Pressure.

Head Pressure Too L ow.

Excessive Suction Pressure.

Suction Pressure Too L ow.

Tabl e 6 – Heating and Cooling Troubleshooting

Power failure. Call power company.

Fuse blown or circuit breaker tripped. Replace fuse or reset circuit breaker. Determine root cause.

Defective thermostat, contactor, transformer, control relay, or capacitor.

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.

High pressure switch tripped. See problem ‘‘Excessive head pressure.’’

Low pressure switch tripped. Check system for leaks. Repair as necessary.

Freeze-up protection thermostat tripped. See problem ‘‘Suction pressure too low.’’

Fault y wiring or loose connections in compressor circuit.

Compressor motor burned out, seized, or internal overload open.

Defective run/start capacitor, overload, start relay.

Onelegof3-phasepowerdead. Replace fuse or reset circuit breaker. Determine cause.

Refrigerant overcharge or undercharge. Recover refrigerant, evacuate system, and recharge to nameplate.

Defective compressor. Replace and determine cause.

Insufficient line voltage. Determine cause and correct.

Blocked outdoor coil or dirty air filter. Determine cause and correct.

Defective run/start capacitor, overload, or start relay.

Defective thermostat. Replace thermostat.

Faulty outdoor-fan (cooling) or indoor-fan (heating) motor or capacitor.

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 (cooling). Reset thermostat.

Low refrigerant charge. Locate leak; repair and recharge.

Air in system. Recover refrigerant, evacuate system, and recharge.

Outdoor coil dirty or restricted. Clean coil or remove restriction.

Compressor rotating in the wrong direction. Reverse the 3-phase power leads as described in

Dirty outside air or return air filter (heating). Replace filter.

Dirty outdoor coil (cooling). Clean coil.

Refrigerant overcharged. Recover excess refrigerant.

Air in system. Recover refrigerant, evacuate system, and recharge.

Condensing air restricted or air short-cycling. Determine cause and correct.

Low refrigerant charge. Check for leaks; repair and recharge.

Compressor scroll plates defective. Replace compressor.

Restrictioninliquidtube. Remove restriction.

High heat load. Check for source and eliminate.

Compressor scroll plates defective. Replace compressor.

Refrigerant overcharged. Recover excess refrigerant.

Dirty air filter (cooling). Replace filter.

Dirty or heavily iced outdoor coil (heating). Clean outdoor coil. Check defrost cycle operation.

Low refrigerant charge. Check for leaks; repair and recharge.

Metering device or low side restricted. Remove source of restriction.

Insufficient indoor airflow (cooling mode). Increase air quantity. Check filter and replace if necessary.

Temperature too low in conditioned area. Reset thermostat.

Field-installed filter drier restricted. Replace.

Outdoor ambient below 25_F (cooling). Install low-ambient kit.

Outdoor fan motor(s) not operating (heating). Check fan motor operation.

Replace component.

Check wiring and repair or replace.

Determine cause. Replace compressor or allow enough time for internal overload to cool and reset.

Determine cause and replace compressor.

Determine cause and replace.

Replace.

Start-Up.

CONVENIENCE OUTLETS

WARNING

Mount the weatherproof cover to the backing plate as shown in Fig. 23. Remove two slot fillers in the bottom of the cover to permit servi ce tool cords to exit the cover. Check for full closing and latching.

ELECTRICAL OPERATION HAZARD

Failure to follow this warning could result in personal injury or death.

Tw o types of convenience outlets are offered on 548J models: Non--powered and unit--powered. Both types provide a 125--volt GFCI (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. 22.

Pwd-CO

Convenience

Outlet

GFCI

Pwd-CO

Fuse

Switch

Transformer

COVER – WHILE-IN-USE WEATHERPROOF

RECEPTACLE NOT INCLUDED

BASE PLATE FOR GFCI RECEPTACLE

C09022

Fig. 23 -- Weatherproof Cover Installation

Non--powered type: This type requires the field

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 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.

548J

Control Box

Access Panel

C08128

Fig. 22 -- Convenience Outlet Location

Installing Weatherproof Cover –

A weatherproof while-in-use cover for the factory-installed convenience outlets is now required by UL standards. This cover cannot be factory-mounted due its depth; it must be installed at unit installation. For shipment, the convenience outlet is covere d with a blank cover plate.

The weatherproof cover kit is shipped in the unit’s control box. The kit includes the hinged cover, a backing plate and gasket.

DISCONNECT ALL POWER TO UNIT AND CONVENIENCE OUTLET.

Remove the blank cover plate at the conveni ence out let; discard the blank cover.

Loosen the two screws at the GFCI duplex outlet, until

approximately

/2-in (13 mm) under screw heads are exposed. Press the gasket over the screw heads. Slip the backing plate over the screw heads at the keyhole slots and align with the gasket; tighten the two screws until snug (do not over-tighten).

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. 22.

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--side terminals on the unit--mounted non--fused disconnect or HACR breaker switch; this will provide service power to the unit when t he 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. 24.

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, 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).

Test the GFCI receptacle by pressing the TEST button on the face of the receptacle to trip and open the receptacle. Check for proper grounding wires a nd power line phasing

if the GFCI receptacle does not trip as required. Press the RESET button to clear the tripped condit ion.

548J

UNIT

VOLTAGE

208,

230

460 480

575 600

CONNECT

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

H2 + H3

Terminals are clearly marked on the board surface. See Fig 25.

The CTB contains no software and no logic. But it does include seven configuration jumpers that are cut to configure the board to read external optional and accessory controls, including that the unit is a heat pump.

CO8283

H1 H2

Fig. 24 -- Powered Convenience Outlet Wiring

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 al so checked and de--energization is confirmed. Observe National Electrical Code Article 210, Branch Circuits, for use of convenience outlets.

HEAT PUMP CONTROLS

Controls Terminal Board

The Controls Terminal Board (CTB) is a large printed circuit board that is located in the center of the unit control box. This printed circuit board contains multiple termination strips and connectors to simplify factory control box wiring and field control connections.

C09274

Fig. 25 -- Controls Terminal Board (CTB)

Table 7 – Jumper Configuration

Jumper Control Function Note

JMP1 Phase Monitor JMP2 Occupancy Control JMP3 Smoke Detector Shutdown JMP4 Remote Shutdown JMP5 Heat Pump / Reheat 548J default: Cut JMP6 Heat Pump / Reheat 548J default: Cut JMP7 Heat Pump / Reheat 548J default: Cut

Jumpers JMP5, JMP6 and JMP7 are located in notches across the top of the CTB (see Fig. 25 ). These jumpers are factory cut on all heat pump units. Visually check these jumpers to confirm that they have been cut.

PROTECTIVE CONTROLS

Compressor Protection

Overcurrent

The compressor has internal linebreak motor protection.

Overtemperature

The compressor has an internal protec tor to protect it against excessively high discharge gas temperatures.

High Pressure

Switch

The system is provided with a high pressure switch mounted on the discharge line. The switch is 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).

Loss of Charge

Switch

The system is protected against a loss of charge and low evaporator coil loading condition by a loss of charge switch located on the liquid line and a freeze protection thermostat on the indoor coil . The switch is stem--mounted. Loss of Charge Switch trip setting is 27 psig +/-- 3 psig (186 +/-- 21 kPa). Re set is automatic at 44 +/-- 3 psig (303 +/-- 21 kPa).

Freeze Protection Thermostat trip setting is 30_F+/--5_F (-- 1_C+/--3_C). Reset is automatic at 45_F+/--5_F(7_C +/--3_C).

Supply (Indoor) Fan Motor Protection

Disconnect and lockout power when servicing fan motor.

2.9 and 3.7 bhp motors are equipped with an overtemperature or protection device. The type of devi ce depends on the motor size. See Table 8.

Table 8 – Overload Device per Motor Size

Motor Size (bhp) Overload Device Reset

1.7 Internal Linebreak Automatic

2.4 Internal Linebreak Automatic

2.9 Thermix Automatic

3.7 Thermix Automatic

4.7

External

(Circuit Breaker)

Manual

Troubleshooting supply fan m otor overload trips: The supply fan used in 548J units is a forward--c urved centrifugal wheel. At a constant wheel speed, this wheel had a characteristic that causes the fan shaft load to DECREASE when the static pressure in the unit--duct system increases and to INCREASE when the static pressure in the unit--duct system decreases (and fan airflow rate increases). Motor overload conditions typically develop when the unit is operated with an access panel removed, with unfinished duct work, in an economizer--open mode, or a leak de velops in the duct system that allows a bypass back to unit return opening.

Outdoor Fan Motor Protection

The outdoor fan motor is internally protected against overtemperature.

Control Circuit, 24--V

548J

The control circuit is protected against overcurrent conditions by a circuit breaker mounted on control transformer TRAN. Reset is manual.

COMMERCIAL DEFROST CONTROL

The Commercial Defrost Control Board (DFB) coordinates thermostat demands for supply fan control, 1 or 2 stage cooling, 2 stage heating, emergency heating and defrost control with unit operating sequences. The DFB also provides an indoor fan off delay feature (user selectable). See Fig. 26 for board arrangement.

The High Static option supply fan motor is equipped with a pilot--circuit Thermix combination overtemperature/ overcurrent protection device. This device resets automatically. Do not bypass this switch to correct trouble. Determine the cause and correct it.

The Thermix device is a snap--action overtemperature protection device that is imbedded in the m otor windings. It is a pilot--circuit device that is wired into the unit’s 24–v control circuit. When this switch reaches its trip setpoint, it opens the 24–v control circuit and causes all unit operation to cease. This device resets automatically when the motor windings cool. Do not bypass this switch to correct trouble. Determine the cause and correct it.

The External motor overload device is a specially--calibrated circuit breaker that is UL recognized as a motor overload controller. It is an overcurrent device. When the motor current exceeds the circuit breaker setpoint, the device opens all motor power le ads and the motor shuts down. Reset requires a manual reset at the overload switch. This device (designated IFCB) is located on the side of the supply fan housing, behind the fan access panel.

DIP Switches

Speed-Up Jumpers

C09275

Fig. 26 -- Defrost Control Board (DFB) Arrangement

The DFB is located in the 548J’s main control box (see Fig. 27). All connections are factory--made through harnesses to the unit’s CTB, to IFC (belt--drive mot or) or to ECM (direct--drive motor), reversing valve solenoids and to defrost thermostats. Refer to Table 9 for details of DFB Inputs and Outputs. Detailed unit operating sequences are provided in the Operating Sequences section starting on page 62.

548J

C09276

Fig. 27 -- Defrost Control Board (DFB) Location

Table 9 – 548J Defrost Board I/O and Jumper Configurations

Inputs

Point Name Type of I/ O Connection Pin Number Unit Connection Note

GFan D I , 2 4 --- v ac P 2 --- 3 LC T B --- G Y1 Cool 1 D I , 2 4 --- v ac P 2 --- 5 LC TB --- Y 1 Y2 Cool 2 D I , 2 4 --- v ac P 2 --- 4 LC TB --- Y 2 W1 Heat 1 D I , 2 4 --- v ac P 2 --- 7 L C T B --- W 1 W2 Heat 2 D I , 2 4 --- v ac P 2 --- 6 L C T B --- W 2 RPower 2 4 --- v ac P 3 --- 1 C O N T L B R D --- 8 C Common 2 4 --- v ac P 3 --- 2 C O N T L B R D --- 4 DFT1 D I , 2 4 --- v a c D F T --- 1 t o D F T --- 1 DFT 2 D I , 2 4 --- v a c D F T --- 2 t o D F T --- 2

Outputs

Point Name Type of I/ O Connection Pin Number Unit Connection Note

IFO Fan On D O , 2 4 --- v a c P 3 --- 9 R E H E AT --- 2 OF OD Fan On DO , 2 4 --- v a c OF OFR RVS1 DO , 2 4 --- v a c P 3 --- 7 t o P 3 --- 5 Energize in COOL RVS2 DO , 2 4 --- v a c P 3 --- 6 t o P 3 --- 4 Energize in COOL COMP 1 DO , 2 4 --- v ac P 3 --- 1 0 FP T --- R E H E A T --- 6 COMP 2 DO , 2 4 --- v ac P 3 --- 8 R E H E AT --- 8 HEAT 2 D O , 2 4 --- v ac E --- H E A T HC --- 1 ( T B 4 --- 1 ) COM 2 4 --- v ac P 3 --- 3 H C --- 1 ( T B 4 --- 3 )

Configuration

Point Name Type of I/ O Connection Pin Number Unit Connection Note

Select Jumper 2 4 --- v ac P 1 --- 1 2 Compressor 2 4 --- v ac P 1 --- 3 Use for 548J***D

Speed--Up Configuration

Point Name Type of I/ O Connection Pin Number Unit Connection Note

Speed---Up Jumper JMP17 Speed---Up Jumper JMP18

Jumper for 1--3 secs: Factory Test, defrost runs for 9 secs Jumper for 5--20 secs: Forced Defrost, defrost runs for 30 secs if DFT2 is open

Reversing valve control — The DFB has two outputs for unit reversing val ve control. Operation of the reversing valves is based on internal logic; this application does not use an “O” or “B” signal to determine reversing valve position. Re versing valves are energized during the Cooling stages and de--energized during Heating cycles. Once energized at the start of a Cooling stage, the reversing valve will remain energized until the next Heating cycle demand is received. Once de--energized at the start of a Heating cycle, the reversing valves will

remain de -- energized until the next Cooling stage is initiated.

Compressor control — The DFB receives inputs indicating Stage 1 Cooling, Stage 2 Cooling (sizes 08 and 09 only) and Stage 1 Heati ng from the space thermostat or unit control system (RTU--MP); it generates commands to start compressors with or without reversing valve operation to produce Stage 1 Cooling (one compressor), Stage 2 Cooling (both compressors run) or Stage 1 Heating (both compressors run).

Auxiliary (Electric) Heat control — The 548J unit can be equipped with one or two auxiliary electric heaters, to provide a second stage of Heating. The DFB will energize this Heating system for a Stage 2 Heating command (heaters operate concurrently with both compressors in the Stage 2 Heating cycle), for an Emergency Heating sequence (compressors are off and only the electric heaters are energized) and also during the Defrost cycle (to eliminate a “cold blow” condition in the space).

Defrost — The defrost control mode is a time/temperature sequence. There are two time components: The continuous run period and the test/defrost cycle period. The temperature component is provided by the defrost thermostat(s) (DFT1 and DFT2 (08--09 only) mounted on the outdoor coil.

still open, the defrost test/run window is closed and the control repeats the continuous run period. If DFT2 is closed, the defrost cycle is initiated in Circuit 2. The defrost period will end when DFT2 opens (indicating the outdoor coil has been cleared of frost and ice) or a 10 minute elapsed period expires, whic hever comes first.

On sizes 08--09, Circuit 1’s defrost ther mostat DFT1 (located on the upper circuit of the outdoor coil) cannot initiate a unit defrost cycle; only DFT2 may do this. But once Circuit 2 is in defrost, the DFB will monitor the status of DFT1. If DFT1 closes during a Circuit 2 defrost cycle, Circuit 1 will also enter a defrost cycle. Circuit 1’s defrost cycle will end when DFT1 opens (indicating the upper portion of the outdoor coil is cleared of frost and ice) or the Circuit 2 defrost cycle is terminated.

The continuous run period is a fixed time period between the end of the last defrost cycle (or start of the current Heating cycle) during which no defrost will be permitted. This period can be set at 30, 60, 90 or 120 minutes by changing the positions of DIP switches SW1 and SW2 (see Fig. 28 and Table 10). The default run periods are 30 minutes for unit sizes 04--07 and 90 minutes for unit sizes 08--09.

C09283

Fig. 28 -- DIP Switch Settings — Defrost Board

At the end of the continuous run period, the defrost control will test for a need to defrost. On unit sizes 04--07 (single compressor designs), DFT1 controls the start and termination of the defrost cycle. If DFT1 is still open, the defrost test/run window is closed and the control repeats the continuous run period. If DFT1 is closed, the defrost cycle is initiated. The defrost period will end when DFT1 opens (indicating the outdoor coil has been cleared of frost and ice) or a 10 minute elapsed period expires, whichever comes first.

On unit sizes 08 and 09 (two circuit designs), DFT2 (located on the bottom circuit of the outdoor coil) controls the start and termination of the defrost cycle. If DFT2 is

At the end of the unit defrost cycle, t he unit will be returned to Heating cycle for a full continuous run period.

If the space heating load is satisfied and compressor operation is terminated, the defrost control will remember where the run period was interrupted. On restart in Heating, the defrost control will resume unit operation at the point in the run period where it was last operat ing.

Defrost Thermostats — These are temperature switches that monitor the surface temperature of the outdoor coil circuits. These switches a re mounted on the liquid tube exiting the outdoor coil heating circuits. These switches close on temperature drop at 30_F(--1_C) and reset open on temperature rise at 80_F(27_C).

Indoor Fan Off Delay — The DFB can provide a 30 sec delay on Indoor Fan Off if the thermostat’s fan selector switch is set on AUTO control. DIP Switch SW3 on the DFB selects use of the fan off time delay feature. Setting SW3 in the OPEN position turns the Fan Off Delay feature on; setting SW3 in the CLOSED position disables this feature. The delay period begins when Y1 demand or W1 demand by the space thermostat is removed.

Defrost Speedup Functions — The DFB permits the servicer to speed--up the defrost cycle. There are two speed--up sequences: relative speed--up and an immediate forced defrost. Speed-- up sequences are initiated by shorting jumper wires JMP17 and JMP18 together (see Fig. 26); use a straight--edge screwdriver.

Shorting the jumpers for a period of 1 to 3 secs reduces the defrost timer periods by a factor of 0.1 sec/minute. (For example, the 90 min run period is reduced to 9 secs.) The DFB will step the unit t hrough a Heating cycle and a Defrost cycle using these reduced time periods. This mode ends after the Defrost cycle.

548J

Table 10 – Dip Switch Position

Switch No.

12 12 12 12 3

0 J J 0 J 0 J 0 0 J Off

90 minutes

1 J 1 J 1 J J 1 On

60 minutes 30 minutes 120 minutes Fan Delay

Shorting the jumpers for a period of 5 to 20 secs bypasses the remaining continuous run period and places the unit in a Forced Defrost mode. If the controlling DFT is closed when this mode is initiated, the unit will complete a normal defrost period that will terminate when the controlling DFT opens or the 10 minute defrost cycle limit is reached. If the controlling DFT is open when this mode is initiated, the Defrost cycle will run for 30 secs. Both modes end at the end of the Defrost cycle.

ELECTRIC HEATERS

548J units may be equipped with field--installed accessory electric heaters. The heaters are modular in design, with heater frames holding open coil resistance wires strung through ceramic insulators, line--break limit switches and a control contact or. One or two heater modules may be used in a unit.

548J

DISCONNECT MOUNTING LOCATION

Unit heaters are marked with Heater Model Numbers. But heaters are ordered as and shipped in cartons marked with a corresponding heater Sale s Package part number. See Table 11 for correlation between heater Model Number and Sales Package part number.

NOTE: The value in position 9 of the part number differs between the sales package part number (value is 1) and a bare heater model number (value is 0).

DISCONNECT MOUNTING LOCATION

MAIN CONTROL BOX

EMT OR RIGID CONDUIT (FIELD-SUPPLIED)

BRACKET AND CONDUIT DRIP BOOT

SINGLE POINT BOX

SINGLE POINT BOX MOUNTING SCREW

CONTROL WIRE TERMINAL BLOCK

HEATER MODULE (LOCATION 1)

CENTER

MANUAL RESET

POST

LIMIT SWITCH

HEATER MODULE (LOCATION 2)

HEATER COVERS

HEATER MOUNTING BRACKET

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Fig. 30 -- T ypical Component Location

UNIT BLOCK-OFF PAN EL

OUTDOOR ACCESS PANEL

INDOOR ACCESS PAN EL

C08133

Fig. 29 -- Typical Access Panel Location (3--6 Ton)

Heater modules are installed in the compa r tment below the indoor (supply) fan outlet. Access is through the indoor access panel. Heater modules slide into the compartment on tracks along the bottom of the heater opening. See Fig. 29, Fig. 30 and Fig. 31.

Not all available heater modules may be used in every unit. Use only those heater modules that are UL listed for use in a specific size unit. Refe r to t he label on the unit cabinet re approved heaters.

Fig. 31 -- T ypical Module Installation

Table 11 – Heater Model Number

Bare Heater Model Number C R H E A T E R 0 0 1 A 0 0

Heater Sales Package PNO Includes:

Bare Heater Carton and packing materials Installation sheet

C R H E A T E R 1 0 1 A 0 0

TRACK

FLANGE

C08135

Single Point Boxes and Supplementary Fuses — When the unit MOCP device value exceeds 60--A, unit--mounted supplementary fuses are required for each heater circuit. These fuses are included in accessory Single Point Boxes, with power distribution and fuse blocks. The single point box will be installed directly under the unit control box, just to the left of the partition separating the indoor section (with electric heaters) from the outdoor section. The Single Point Box has a hinged access cover. See Fig. 32.

CONTROL BOX

BUSHING

SINGLE POINT BOX MOUNTING SCREWS

DRIP BOOT BRACKET MOUNTING SCREWS

POWER WIRES

FOAM BUSHING

HEATER RELAYS

HEATER MOUNTING SCREWS

A L

LIE

P A

C O

R P .

M O DE

N O .

ERI

A L

N O.

2 . 2

ISTED

AIR

NDITIONING

1 2 3

UIP

ACCESS

346N

P / N

REV

C08136

Fig. 32 -- Typical Single Point Installation

On 548J units, all fuses are 60--A. Single point boxes containing fuses for 208/230--V applications use UL Class RK5 250--V fuses (Bussman FRNR 60 or Shawmut TR 60R). Single point boxes for 460--V and 575--V applications use UL Class T 600--V fuses (Bussman JJS 60 or Shawmut A6T 60). (Note that all heaters are qualified for use with a 60--A fuse, regardless of actual heater ampacity, so only 60--A fuses are necessary.)

Unit heater applications not requiring supplemental fuses require a special Single Point Box without any fuses. Connect power supply conductors to heater conductors and field--supplied base unit power tap leads (see text below re: “Completing Heater Installati on”) inside the empty Single Point Box using UL--approved connec tors.

Safety Devices — Electric heater applications use a combination of line-- break/auto--reset limit switches and a pilot--circuit/manual reset limit switch to protect the unit against over--temperature situations.

Line--break/auto-- reset limit switches are mounted on the base plate of each heater module. See Fig. 33. These are accessed through the indoor access panel. Remove the switch by removing two screws into the base plate and extracting the existing switch.

Pilot--circuit/manual reset limit switch is located in the side plate of the indoor (supply) fan housing. See Fig. 30.

Completing Heater Installation

Field Power Connections — Tap conductors must be

installed between the base unit’s field power connection lugs and the Single Point Box (with or without fuses). Refer to unit wiring schematic. Use copper wire only. For

connection using the Single Point Box less fuses, connect the field power supply conductors to the heater power leads and the field--supplied tap conductors inside the Single Point Box. Use UL--approved pressure connectors (field--supplied) for these splice joints.

Line-Break Limit Switches

ALLIED P

MODE

NO.

ERIAL

NO.

ISTED

AIR

NDITIONING

ACCESS

/ N

5610-4

C08330

Fig. 33 -- Typical Location of Heater Limit Switches

(3--phase heater shown)

Low--Voltage Control Connections — Pull the

low--voltage control leads from the heater module(s) -VIO and BRN (two of each if two modules are installed; identify for Module #1) -- to the 4--pole terminal board TB4 located on the heater bulkhead to the left of Heater #1. Connect the VIO lead from Heater #1 to terminal TB4--1. Connect the VIO lead from Heater #2 to terminal TB4--2. Connect both BRN leads to terminal TB4--3. See Fig. 34.

DEFROST

BOARD

E-HEAT

P3-3

ORN

BRN

ORN BRN

TB4

Field Connections

VIO BRN BRN

VIO

Elec Htr

VIO HR2

VIO BRN

BRN

HR1

HR1: On Heater 1 in Position #1 HR2: On Heater 2 in Position #2 (if installed)

C09013

Fig. 34 -- Accessory Electric Heater Control

Connections

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SMOKE DETECTORS

Sensor

Smoke detectors are a vailable as factory-- installed options on 548J 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 compone nts necessary for operation are fa ctory--provided and mounted. The unit is factory--configured for immediate smoke detector shutdown operation; additional wiring or modificati ons 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

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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. 35) 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).

The sensor (see Fig. 36) includes a pla stic 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 ha ving to disassemble the sensor. The cover attaches to the sensor housing using four captive screws and forms an airtight cham ber 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).

Duct smoke sensor

Exhaust tube

See

Detail A

Intake

gasket

Plug

TSD-CO2

(ordering option)

Sampling tube

(ordered separately)

Exhaust gasket

Sensor housing and electr onics

Cover gasket

(ordering option)

Sensor cover

Controll er housing

and electronics

Conduit c ouplings

(supplie d by installer)

Duct smoke sensor

controller

Conduit nuts

(supplie d by installer)

Conduit s upport plate

Terminal block cover

Fastener

(2X)

Alarm

Troub le

Power

Tes t / r e s e t switch

Fig. 35 -- Controller Assembly

Cover gasket

(ordering option)

Controll er cover

C08208

Magnetic test/reset

switch

Coupling

Alarm

Troub le

Power Dirty

C08209

Detail A

Fig. 36 -- Smoke Detector Sensor

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.

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. 37. Access is through the fan access panel. There is no sampling tube used at this location. The sampling tube inlet extends through the side plat e 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.

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. 39. The holes in the sampling tube face downward, into the return air stream. The sampling tube is connected via tubing t o the return a ir 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 re located to its operating location and the tubing to the sampling tube be connected. See “Completing Installation of Return Air Smoke Sensor” for installation steps.)

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Return Air Sampling Tube

Smoke Detector Sensor

C08245

Fig. 37 -- T ypical Supply Air Smoke Detector Sensor

Location

Return Air without Economizer — The sampling tube is located across the return air opening on the unit basepan. See Fig. 38. 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 re located to its operating location and the tubing to the sampling tube be connected. See “Completing Installation of Return Air Smoke Sensor” for installation steps.)

Return Air Detector module (shipping position shown)*

Controller module

Return Air Detector Sampling Tube

*RA detector must be moved from shipping position to operating position by installer

C07307

Fig. 38 -- Typical Return Air Detector Location

C08129

Fig. 39 -- Return Air Sampling Tube Location

Completing Installation of Return Air Smoke Sensor:

SCREWS

EXHAUST TUBE

FLEXIBLE EXTENSION TUBE

SAMPLING

C08126

Fig. 40 -- Return Air Detector Shipping Position

1. Unscrew the two screws holding the Return Air Sensor detector plate. See Fig. 40. 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 t he sampling tube connecti on is on the bottom. See Fig. 41.

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 bot tom and the exhaust tube is on the top. See Fig. 41.

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.

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Fig. 41 -- Return Air Sensor Operating Position

FIOP Smoke Detector Wiring and Response

All units: FIOP smoke detector is configured to automatically shut down all unit ope rations when smoke condition is detected. See Fig. 42, Typical Smoke Detector System Wiring.

Highlight A: JMP 3 is factory--cut, transferring unit control to smoke detector.

C08127

Highlight B: Smoke detector NC contact set will open on smoke al arm condition, de--energizing the ORN conductor.

Highlight C: 24--v power signal via ORN lead is removed at Smoke Detector input on CTB (Control Terminal Board); all unit operations cease immediately.

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 CTB provides 24--v signal to FIOP DDC control.

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 in Fig. 42) for additional annunciation functions.

Additional Application Data — Refer to Cat alog No. HKRNKA--1XA for discussions on additional control features of these smoke detectors including multiple unit coordination. See Fig. 42.

Fig. 42 -- Typical Smoke Detector System Wiring

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 the factory provided SD--MAG test magnet. The magnet (which is approximately 1.0 in. long. x plastic bag in the unit control box.

CAUTION

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n 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, notify the proper authorities before 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 t est magnet against the sensor housing for two seconds.

4. Verify that the sensor’s Alarm LED turns off.

/4in. sq.) is located in a

Controller Alarm Test

The controller alarm test checks the controller’s ability to initiate and indicate an a larm state.

CAUTION

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n 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 Test

The dirty controller test checks the controller’s ability to initiate a dirty sensor test and indicate its results.

CAUTION

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n personnel and authority concern.

Pressing the controller’s test/reset switch for longer than seven seconds will put the duct detector i nto 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 Test

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 the factory 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 12.

CAUTION

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n 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.

Tabl e 12 – D i rty L ED Te st

FLASHES DESCRIPTION

1 0---25% dirty. (Typical of a newly installed detector) 2 25- -- 50% dirty 3 51- -- 75% dirty 4 76- -- 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.

548J

CAUTION

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n 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 Dirty Sensor Test

By default, sensor dirty test results are indicated by:

S The sensor’s Dirty LED flashing. S The controller’s Trouble LED fla shing.

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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 Test

The remote station alarm test checks a test/reset station’s ability to initiate and indicate an alarm state.

CAUTION

Remote Test/Reset Station Dirty Sensor Test

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. 43 and configured to operate the controller’s supervision relay. For more information, see “Changing the Dirty Sensor Test.”

Wire must be

added by installer

TB3

Supervision relay contacts [3]

Fig. 43 -- Remote Test/Reset Station Connections

CAUTION

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n 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.

Smoke Detector Controller

–

Auxiliary

equipment

18 Vdc (+)

18 Vdc (

–

)

CRSDTEST001A00

Tro uble

Power

Alarm

Reset/ Test

C09326

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n personnel and authority concern.

CRSDTEST001A00 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 turni ng the key switch to the RESET/TEST position for two seconds.

4. Verify that the test/reset station’s Alarm LED turns off.

CAUTION

OPERATIONAL TEST HAZARD

Failure to follow this caution may result i n 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.

Dirty Sensor T est Using an CRSDTEST001A00

1. Turn the key switch to the RESET/TEST position for two seconds.

2. Verify that the test/reset stat ion’s Trouble LED flashes.

+ 70 hidden pages

Bryant 548J User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual