Carrier 50VL-A User Manual

50VL---A
Performancet 14 SEER Single---Packaged Air Conditioner
System with Puron® (R ---410A) Refrigerant
Single and Three Phase
2 --- 5 N o m i n a l To n s ( S i z e s 2 4 --- 6 0 )

Installation Instructions

NOTE: Read the entire instruction manual before starting the
installation.

NOTE: Installer: Make sure the Owner’s Manual and Service
Instructions are left with the unit after installation.

TABLE OF CONTENTS

PAGE

SAFETY CONSIDERATIONS 1--2.......................

INTRODUCTION 2...................................

RECEIVING AND INSTALLATION 2--10.................

Check Equipment 2..................................

Identify Unit 2....................................

Inspect Shipment 2.................................

Provide Unit Support 2...............................

Roof Curb 2......................................

Slab Mount 2.....................................

Provide Clearances 7.................................

Field Fabricate Ductwork 7............................

Rig and Place Unit 7.................................

Inspection 7......................................

Rigging/Lifting of Unit 7............................

Connect Condensate Drain 8...........................

Install Duct Connections 8.............................

Configuring Units for Downflow (Vertical) Discharge 8....

Install Electrical Connections 9.........................

High--Voltage Connections 9.........................

Special Procedures for 208v Operation 10...............

Control Voltage Connections 10.......................

Standard Connection 10.............................

Transformer Protection 10...........................

PRE--START--UP 12...................................

START--UP 12--14.....................................

Check for Refrigerant Leaks 12.........................

Start--Up Adjustments 12..............................

Checking Cooling Control Operation 12................

Checking and Adjusting Refrigerant Charge 12...........

Indoor Airflow and Airflow Adjustments 13.............

Continuous Fan Operation 14........................

Cooling Sequence of Operation 14.....................

MAINTENANCE 24--2 6................................

Air Filter 24......................................

Indoor Blower and Motor 24.........................

Outdoor Coil, Indoor Coil, and Condensate Drain Pan 25...

Outdoor Fan 25...................................

Electrical Controls and Wiring 25.....................

Refrigerant Circuit 26...............................

Evaporator Airflow 26..............................

Puron Items 26....................................

TROUBLESHOOTING 27..............................

START--UP CHECKLIST 27............................

Improper installation adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury, or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory-- authorized kits or accessories
when modifying this product Refer to the individual instructions
packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Use quenching cloth for brazing operations.
Have a fire extinguisher available. Read these instructions
thoroughly and follow all warnings or cautions included in
literature and attached to the unit. Consult local building codes, the
current editions of the National Electrical Code (NEC) NFPA 70.
In Canada refer to the current editions of the Canadian electrical
Code CSA C22.1.

Recognize safety information. This is the safety--alert symbol
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury. Understand
these 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 hazards 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.

SAFETY CONSIDERATIONS

A09033

Fig. 1 -- Unit 50VL --A

.

1

!

WARNING

ELECTRICAL SHOCK HAZARD

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

Before installing or servicing system, always turn off main
power to system and install lockout tag. There may be
more than one disconnect switch. Turn of f accessory heater
power switch if applicable.

!

WARNING

PERSONAL INJURY AND ENVIRONMENTAL
HAZARD

Failure to relieve system pressure could result in personal
injury and/or death.

1. Relieve pressure and recover all refrigerant before

50VL -- A

servicing existing equipment, and before final unit disposal.
Use all service ports and open all flow--control devices,
including solenoid valves.

2. Federal regulations require that you do not vent
refrigerant into the atmosphere. Recover during system
repair or final unit disposal.

!

CUT HAZARD

Failure to follow this caution may result in personal injury.

When removing access panels (see Fig. 17) or performing
maintenance functions inside your unit, be aware of sharp
sheet metal parts and screws. Although special care is taken
to reduce sharp edges to a minimum, be extremely careful
when handling parts or reaching into the unit.

CAUTION

INTRODUCTION

The 50VL --A packaged air conditioner is fully self--contained and
designed for outdoor installation (See Fig.1 ). See Fig. 2 and 3 for
unit dimensions. All unit sizes have discharge openings for both
horizontal and downflow configurations, and are factory shipped
with all downflow duct openings covered. The unit may be
installed either on a rooftop or on a ground--level cement slab. (See
Fig. 4 for roof curb dimensions.)

RECEIVING AND INSTALLATION

Step 1 — Check Equipment

IDENTIFY UNIT

The unit model number and serial number are printed on the unit
informative plate. Check this information against shipping papers.

INSPECT SHIPMENT

Inspect for shipping damage before removing packaging materials.
If unit appears to be damaged or is torn loose from its anchorage,
have it examined by transportation inspectors before removal.
Forward claim papers directly to transportation company.
Manufacturer is not responsible for any damage incurred in transit.
Check all items against shipping list. Immediately notify the
nearest equipment distribution office if any item is missing. To
prevent loss or damage, leave all parts in original packages until
installation.

If the unit is to be mounted on a curb in a downflow application,
review Step 7 to determine which method is to be used to remove
the downflow panels before rigging and lifting into place. The
panel removal process may require the unit to be on the ground.

Step 2 — Provide Unit Support

IMPORTANT: The unit must be secured to the curb by installing

screws through the bottom of the curb flange and into the unit base
rails. When installing large base units onto the common curb, the
screws must be installed before allowing the full weight of the unit
to rest on the curb. A minimum of six screws are required for large
base units. Failure to secure unit properly could result in an
unstable unit. See Warning near Rigging/Lifting information and
accessory curb instructions for more details.

For hurricane tie downs, contact distributor for details and PE
(Professional Engineering) Certificate if required.

ROOF CURB

Install accessory roof curb in accordance with instructions shipped
with curb (See Fig. 4). Install insulation, cant strips, roofing, and
flashing. Ductwork must be attached to curb.
IMPORTANT: The gasketing of the unit to the roof curb is
critical for a water tight seal. Install gasketing material supplied
with the roof curb. Improperly applied gasketing also can result in
air leaks and poor unit performance.
Curb should be level to within 1/4 in. (6.35 mm) (See Fig 6). This
is necessary for unit drain to function properly. Refer to accessory
roof curb installation instructions for additional information as
required.

Installation on older “G” series roof curbs.

Two accessory kits are available to aid in installing a new “G”
series unit on an old “G” roof curb.

1. Accessory kit number CPADCURB001A00, (small chassis)
and accessory kit number CPADCURB002A00, (large
chassis) includes roof curb adapter and gaskets for the
perimeter seal and duct openings. No additional
modifications to the curb are required when using this kit.

2. An alternative to the adapter curb is to modify the existing
curb by removing the outer horizontal flange and use
accessory kit number CPGSKTKIT001A00 which includes
spacer blocks (for easy alignment to existing curb) and
gaskets for the perimeter seal and duct openings. This kit is
used when existing curb is modified by removing outer
horizontal flange.

!

UNIT/STRUCTURAL DAMAGE HAZARD

Failure to follow this caution may result in property
damage.

Ensure there is sufficient clearance for saw blade when
cutting the outer horizontal flange of the roof curb so there
is no damage to the roof or flashing.

SLAB MOUNT

Place the unit on a solid, level concrete pad that is a minimum of 4
in. (102 mm) thick with 2 in. (51 mm) above grade. The slab
should extend approximately 2 in. (51 mm) beyond the casing on
all 4 sides of the unit (See Fig. 7). Do not secure the unit to the slab
except when required by local codes.

CAUTION

2

50VL -- A

Fig. 2 -- 50VL--A24--36 Unit Dimensions

3

A09462

50VL -- A

Fig. 3 -- 50VL--A42--60 Unit Dimensions

4

A09463

HVAC unit
base rails

Anchor screw

Flashing field
supplied

Roofing material
field supplied

Cant strip
field supplied

HVAC unit
basepan

Sealing
Gasket

Roofcurb

Wood nailer*

Roofcurb*

Insulation
(field supplied)

B

G

C

F

A

H

D

Dashed lines show cross support
location for large basepan units.

E

A09413

50VL -- A

*Provided with roofcurb

ROOF CURB DETAIL

SMALL/COMMON CURB

A09090

B

C

G

A

F

H

E

SUPPLY

AIR

RETURN

AIR

SMALL
BASE
UNIT

LARGE
BASE
UNIT

D

UNIT PLACEMENT ON

LARGE CURB

A09415

COMMON CURB

SMALL OR LARGE BASE UNIT

A09094

UNIT
SIZE

Small

or

Large

CATALOG

NUMBER

CPRFCURB010A00

CPRFCURB011A00

CPRFCURB012A00

Large

CPRFCURB013A00

* Part Numbers CPRCURB010A00 and CPRCURB011A00 can be used on both small an d large basepan units. T he cross supports must be located based on
whether the unit is a small basepan or a large basepan.
NOTES:

1. Roof curb must be set up for unit being installed.

2. Seal strip must be applied, as required, to unit being installed.

3. Roof curb is made of 16 --gauge steel.

4. Attach ductwork to curb (flanges of duct rest on curb).

5. Insulated panels: 1--in. (25.4 mm) thick fiberglass 1 lb. density.

A

IN.

(mm)

11

(279)

14

(356)

11

(279)

14

(356)

B

(small/common

base)

IN. (mm)*

10 (254)

14 (356)

B

(large base)

IN. (mm)*

14 (356)

C

IN.

(mm)

16

(406)

D

IN.

(mm)

47.8

(1214)

E

IN.

(mm)

32.4

(822)

43.9

(1116)

F

IN.

(mm)

2.7

(69)

G

IN. (mm)HIN. (mm)

30.6 (778)

46.1 (1170)

42.2 (1072)

Fig. 4 -- Roof Curb Dimensions

5

A09414

CAUTION - NOTICE TO RIGGERS
PRUDENCE - AVIS AUX MANIPULATEUR

PANNEAUX D'ACCES DOIT ÊTRE EN PLACE POUR MANIPULATION.

Use top skid as spreader bar. / Utiliser la palette du haut comme barre de répartition

ACCESS PANELS MUST BE IN PLACE WHEN RIGGING.

DUCTS

MINIMUM HEIGHT: 36" (914.4 mm)
HAUTEUR MINIMUM

50VL -- A

SEE DETAIL A
VOIR DÉTAIL A

SMALL CABINET LARGE CABINET

Unit*

Rigging

Weight

* For 460 volt units, add 14 lb (6.35 kg) to the rigging weight.
NOTE: See dimensional drawing for corner weighs.

24 30 36

lb kg lb kg lb kg lb kg lb kg lb kg

295 134 307 139 365 166

UNIT HEIGHT
HAUTEUR D'UNITÉ

DETAIL A

VOIR DÉTAIL A

Unit*

Rigging

Weight

421 191 439 199 467 212

Fig. 5 -- 50VL--A Unit Suggested Rigging

SEAL STRIP MUST BE IN
PLACE BEFORE PLACING
UNIT ON ROOF CURB

42 48 60

BANDE SCELLANT DOIT ÊTRE
EN PLACE AVANT DE PLACER
L'UNITÉ SUR LA BASE DE TOIT

50CY502286 2.0

A09051

6

Step 3 — Provide Clearances

A

The required minimum service clearances are shown in Fig. 2 and

3. Adequate ventilation and outdoor air must be provided. The
outdoor fan draws air through the outdoor coil and discharges it
through the top fan grille. Be sure that the fan discharge does not
recirculate to the outdoor coil. Do not locate the unit in either a
corner or under an overhead obstruction. The minimum clearance
under a partial overhang (such as a normal house overhang) is 48
in. (1219 mm) above the unit top. The maximum horizontal
extension of a partial overhang must not exceed 48 in. (1219 mm)
IMPORTANT: Do not restrict outdoor airflow. An air restriction
at either the outdoor--air inlet or the fan discharge may be
detrimental to compressor life.
Do not place the unit where water, ice, or snow from an overhang
or roof will damage or flood the unit. Do not install the unit on
carpeting or other combustible materials. Slab--mounted units
should be at least 4 in. (102 mm) above the highest expected water
and runoff levels. Do not use unit if it has been under water.

Step 4 — Field--Fabricate Ductwork

Secure all ducts to roof curb and building structure on vertical
discharge units. Do not connect ductwork to unit. For horizontal
applications, unit is provided with flanges on the horizontal
openings. All ductwork should be secured to the flanges. Insulate
and weatherproof all external ductwork, joints, and roof openings
with counter flashing and mastic in accordance with applicable
codes.
Ducts passing through an unconditioned space must be insulated
and covered with a vapor barrier. If a plenum return is used on a
vertical unit, the return should be ducted through the roof deck to
comply with applicable fire codes. See unit rating plate for any
required clearances around ductwork. Cabinet return--air static
shall not exceed --.25 IN. W .C.

Step 5 — Rig and Place Unit

Rigging and handling of this equipment can be hazardous for
many reasons due to the installation location (roofs, elevated
structures, etc.).
Only trained, qualified crane operators and ground support staff
should handle and install this equipment.
When working with this equipment, observe precautions in the
literature, on tags, stickers, and labels attached to the equipment,
and any other safety precautions that might apply.
Training for operators of the lifting equipment should include, but
not be limited to, the following:

1. Application of the lifter to the load, and adjustment of the
lifts to adapt to various sizes or kinds of loads.

2. Instruction in any special operation or precaution.

3. Condition of the load as it relates to operation of the lifting
kit, such as balance, temperature, etc.

Follow all applicable safety codes. Wear safety shoes and work
gloves.

INSPECTION

Prior to initial use, and at monthly intervals, all rigging shackles,
clevis pins, and straps should be visually inspected for any damage,
evidence of wear, structural deformation, or cracks. Particular
attention should be paid to excessive wear at hoist hooking points
and load support areas. Materials showing any kind of wear in
these areas must not be used and should be discarded.

!

WARNING

UNIT FALLING HAZARD

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

Never stand beneath rigged units or lift over people.

1. Leave top shipping skid on the unit for use as a spreader bar
to prevent the rigging straps from damaging the unit. If the
skid is not available, use a spreader bar of sufficient length
to protect the unit from damage.

!

WARNING

PROPERTY DAMAGE HAZARD

Failure to follow this warning could result in personal

When straps are taut, the clevis should be a minimum of 36
in. (914 mm) above the unit top cover.

Rigging/Lifting of Unit (See Fig. 5)

!

WARNING

UNIT FALLING HAZARD

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

Large base units must be secured to common curb before
allowing full weight of unit to rest on curb. Install screws
through curb into unit base rails while rigging crane is still
supporting unit.

Lifting holes are provided in base rails as shown.

1. Attach shackles, clevis pins, and straps to the base rails of
the unit. Be sure materials are rated to hold the weight of the
unit (See Fig. 5).

2. Attach a clevis of sufficient strength in the middle of the
straps. Adjust the clevis location to ensure unit is lifted level
with the ground.

After the unit is placed on the roof curb or mounting pad, remove
the top skid.

50VL -- A

OPTIONAL

RETURN

AIR

C

MAXIMUM ALLOWABLE

B

A-B

(6.35)

1/4

Fig. 6 -- Unit Leveling Tolerances

DIFFERENCE in. (mm)

1/4

B-C

(6.35)

A-C

1/4

(6.35)

A07925

(50.8mm)

7

2˝

OPENING

EVAP. COIL COND. COIL

Fig. 7 -- Slab Mounting Detail

OPTIONAL

SUPPLY

AIR

OPENING

A07926

Step 6 — Connect Condensate Drain

NOTE: When installing condensate drain connection be sure to

comply with local codes and restrictions.

Model 50VL-- A disposes of condensate water through a 3/4 in.
NPT fitting which exits through the base on the evaporator coil
access side. See Fig. 2 and 3 for location.

Condensate water can be drained directly onto the roof in rooftop
installations (where permitted) or onto a gravel apron in ground
level installations. Install a field-- supplied 2--in. (51 mm)
condensate trap at end of condensate connection to ensure proper
drainage. Make sure that the outlet of the trap is at least 1 in. (25
mm) lower than the drain pan condensate connection to prevent the
pan from overflowing (See Fig. 8). When using a gravel apron,
make sure it slopes away from the unit.

Connect a drain tube using a minimum of 3/4 -- in. PVC or 3/4 --in.
copper pipe (all field--supplied) at the outlet end of the 2-- in. (51
mm) trap. Do not undersize the tube. Pitch the drain tube
downward at a slope of at least 1 -- in. (25 mm) for every 10 ft (3.1
m) of horizontal run. Be sure to check the drain tube for leaks.
Prime trap at the beginning of the cooling season start--up.

50VL -- A

TRAP
OUTLET

1-in. (25 mm) min.

2-in. (51 mm) min.

Fig. 8 -- Condensate Trap

Step 7 — Install Duct Connections

The design and installation of the duct system must be in
accordance with the standards of the NFPA for installation of
non--residence type air conditioning and ventilating systems,
NFPA 90A or residence type, NFPA 90B and/or local codes and
ordinances.

Select and size ductwork, supply--air registers, and return air grilles
according to ASHRAE (American Society of Heating,
Refrigeration, and Air Conditioning Engineers) recommendations.
The unit has duct flanges on the supply-- and return--air openings
on the side of the unit.

When designing and installing ductwork, consider the following:

1. All units should have field--supplied filters or accessory
filter rack installed in the return--air side of the unit.
Recommended sizes for filters are shown in Table 1.

2. Avoid abrupt duct size increases and reductions. Abrupt
change in duct size adversely affects air performance.

IMPORTANT: Use flexible connectors between ductwork and
unit to prevent transmission of vibration. Use suitable gaskets to
ensure weather--tight and airtight seal. When electric heat is
installed, use fireproof canvas (or similar heat resistant material)
connector between ductwork and unit discharge connection. If
flexible duct is used, insert a sheet metal sleeve inside duct. Heat
resistant duct connector (or sheet metal sleeve) must extend 24--in.
(610 mm) from electric heater element.

3. Size ductwork for cooling air quantity (cfm). The minimum
air quantity for proper electric heater operation is listed in
Table 2. Heater limit switches may trip at air quantities
below those recommended.

4. Seal, insulate, and weatherproof all external ductwork. Seal,
insulate and cover with a vapor barrier all ductwork passing
through conditioned spaces. Follow latest Sheet Metal and

A09052

Air Conditioning Contractors National Association
(SMACNA) and Air Conditioning Contractors Association
(ACCA) minimum installation standards for residential
heating and air conditioning systems.

5. Secure all ducts to building structure. Flash, weatherproof,
and vibration--isolate duct openings in wall or roof
according to good construction practices.

CONFIGURING UNITS FOR DOWNFLOW
(VERTICAL)

ELECTRICAL SHOCK HAZARD

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

Before performing service or maintenance operations on the
system, turn off main power to unit and install lockout tag.

1. Open all electrical disconnects and install lockout tag before
starting any service work.

2. Remove horizontal (metal) ductcovers to access vertical
(downflow) discharge duct knockouts in unit basepan. (See
Fig. 9.)

To remove downflow return and supply knockout covers, break
front and right side connecting tabs with a screwdriver and
hammer. Push cover down to break rear and left side tabs.

NOTE: These panels are held in place with tabs similar to an
electrical knockout. Reinstall horizontal duct covers (Fig. 9)
shipped on unit from factory. Insure openings are air and
watertight.

NOTE: The design and installation of the duct system must be in
accordance with the standards of the NFPA for installation of
nonresidence--type air conditioning and ventilating systems, NFPA
90A or residence--type, NFPA 90B; and/or local codes and
ordinances.

Adhere to the following criteria when selecting, sizing, and
installing the duct system:

1. Units are shipped for side shot installation.

2. Select and size ductwork, supply--air registers, and
return--air grilles according to American Society of Heating,
Refrigeration and Air Conditioning Engineers (ASHRAE)
recommendations.

3. Use flexible transition between rigid ductwork and unit to
prevent transmission of vibration. The transition may be
screwed or bolted to duct flanges. Use suitable gaskets to
ensure weather--tight and airtight seal.

4. All units must have field --supplied filters or accessory filter
rack installed in the return--air side of the unit.
Recommended sizes for filters are shown in Table 1.

5. Size all ductwork for maximum required airflow (either
heating or cooling) for unit being installed. Avoid abrupt
duct size increases or decreases or performance may be
affected.

6. Adequately insulate and weatherproof all ductwork located
outdoors. Insulate ducts passing through unconditioned
space, and use vapor barrier in accordance with latest issue
of Sheet Metal and Air Conditioning Contractors National
Association (SMACNA) and Air Conditioning Contractors
of America (ACCA) minimum installation standards for
heating and air conditioning systems. Secure all ducts to
building structure.

7. Flash, weatherproof, and vibration--isolate all openings in
building structure in accordance with local codes and good
building practices.

DISCHARGE

!

WARNING

8

Horizontal Duct Covers

Basepan
Downflow
(Vertical)
Supply
Knockout

Fig. 9 -- Supply and Return Duct Opening

Step 8 — Install Electrical Connections

!

WARNING

ELECTRICAL SHOCK HAZARD

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

The unit cabinet must have an uninterrupted, unbroken
electrical ground to minimize the possibility of personal
injury if an electrical fault should occur. This ground may
consist of an electrical wire connected to the unit ground
screw in the control compartment, or conduit approved for
electrical ground when installed in accordance with NFPA
70 (NEC) (latest edition) (in Canada, Canadian Electrical
Code CSA C22.1) and local electrical codes.

A09076

Basepan
Downflow
(Vertical)
Return
Knockout

A09093

!

UNIT COMPONENT DAMAGE HAZARD

Failure to follow this caution may result in damage to the
unit being installed.

1. Make all electrical connections in accordance with
NFPA 70 (NEC) (latest edition) and local electrical codes
governing such wiring. In Canada, all electrical
connections must be in accordance with CSA standard
C22.1 Canadian Electrical Code Part 1 and applicable
local codes. Refer to unit wiring diagram.

2. Use only copper conductor for connections between
field--supplied electrical disconnect switch and unit. DO
NOT USE ALUMINUM WIRE.

3. Be sure that high--voltage power to unit is within
operating voltage range indicated on unit rating plate. On
3--phase units, ensure phases are balanced within 2
percent. Consult local power company for correction of
improper voltage and/or phase imbalance.

4. Do not damage internal components when drilling
through any panel to mount electrical hardware, conduit,
etc.

CAUTION

HIGH--VOLTAGE CONNECTIONS

The unit must have a separate electrical service with a
field--supplied, waterproof disconnect switch mounted at, or within
sight from the unit. Refer to the unit rating plate, NEC and local
codes for maximum fuse/circuit breaker size and minimum circuit
amps (ampacity) for wire sizing.

The field--supplied disconnect may be mounted on the unit over
the high--voltage inlet hole when the standard power and
low--voltage entry points are used. See Fig. 2 and 3 for acceptable
location.

See unit wiring label (Fig. 12, 13 and 14) and Fig. 10 for reference
when making high voltage connections. Proceed as follows to
complete the high--voltage connections to the unit.

Single phase units:

1. Run the high-- voltage (L1, L2) and ground lead into the
control box.

2. Connect ground lead to chassis ground connection.

3. Locate the black and yellow wires connected to the line side
of the contactor.

4. Connect field L1 to black wire on connection 11 of the
compressor contactor.

50VL -- A

9

CONTROL BOX

LOW-VOLTAGE
POWER LEADS
(SEE UNIT
WIRING LABEL)

50VL -- A

5.ConnectfieldwireL2toyellowwireonconnection23of

Three--phase units:

1. Run the high--voltage (L1, L2, L3) and ground lead into the

2. Connect ground lead to chassis ground connection.

3. Locate the black and yellow wires connected to the line side

4. Connect field L1 to black wire on connection 11 of the

5.ConnectfieldwireL3toyellowwireonconnection13of

6. Connect field wire L2 to blue wire from compressor.

HIGH VOLTAGE
POWER LEADS
(SEE UNIT WIRING
LABEL

)

3-PHASE SHOWN
1-PHASE USES
TWO POWER
LEADS

EQUIP GR

SPLICE BOX

FIELD-SUPPLIED
FUSED DISCONNECT

WHT(W1)

VIO (W2)

YEL(Y)

GRN(G)

RED(R)

BRN(C)

BLU (DH)

GRA (Y2)

W1

W2

Y

G

R

C

DH

3-Phase
Only

Fig. 10 -- High-- and Control--Voltage Connections

the compressor contactor.

control box.

of the contactor.

compressor contactor.

the compressor contactor.

POWER
SUPPLY

THERMOSTAT
(TYPICAL

A09066

SPECIAL PROCEDURES FOR 208--V OPERATION

!

WARNING

ELECTRICAL SHOCK HAZARD

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

Before installing or servicing system, always turn off main
power to system and install lockout tag. With disconnect
switch open, move black wire from transformer (3/16
in.)(4.8 mm) terminal marked 230 to terminal marked 208.
This retaps transformer to primary voltage of 208 vac.

CONTROL VOLTAGE CONNECTIONS

NOTE: Do not use any type of power--stealing thermostat. Unit

)

control problems may result.

Use no. 18 American Wire Gage (AWG) color--coded, insulated
(35°C minimum) wires to make the control voltage connections
between the thermostat and the unit. If the thermostat is located
more than 100 ft (30.5 m) from the unit (as measured along the
control voltage wires), use no. 16 AWG color--coded, insulated
(35° C minimum) wires.

STANDARD CONNECTION

Locate the seven (eight for 3-- phase) low voltage thermostat leads
in 24 volt splice box. A gray wire is standard on 3--phase units for
connection to an economizer. See Fig. 10 for connection diagram.
Run the low-- voltage leads from the thermostat, through the control
wiring inlet hole grommet (Fig. 2 and 3), and into the low-- voltage
splice box. Provide a drip loop before running wires through panel.
Secure and strain relief all wires so that they do not interfere with
operation of unit.

If an accessory electric heater is installed, low voltage leads from
heater must be connected to factory supplied control leads from
Indoor Fan Board P4 connector.

NOTE: If the unit 24V wires do not have a matching receptacle,
cut the 24V wires from the electric heater plug, strip the ends, and
wire nut together to match the schematic connections. If the electric
heater 24V wires do not have a matching plug, cut the 24V wires
from the unit receptacle, strip the ends, and wire nut together to
match the schematic connections.

Factory wires are provided for electric heat staging W1 and W2
(W2 and W3 on IFB). If room thermostat has only one stage of
supplemental heat, connect white and violet wires shown in Fig. 10
to second stage heat field wire.

Some electric heaters have four control wires (plus common wire).
Consult unit wiring diagram and electric heater wiring diagram for
additional details.

TRANSFORMER PROTECTION

The transformer is of the energy--limiting type, however a direct
short will likely blow a secondary fuse. If an overload or short is
present, correct overload condition and check for blower fuse on
Indoor Fan Board. Replace fuse as required with correct size and
rating.

10

Table 1 – Physical Data--Unit 50VL--A

UNIT SIZE 24 30 36 42 48 60
NOMINAL CAPACITY (ton) 2 2 --- 1 / 2 3 3 --- 1 / 2 4 5
SHIPPING WEIGHT* lb.

SHIPPING WEIGHT* (kg)

COMPRESSORS

Quantity

REFRIGERANT (R--- 410A)

Quantity lb
Quantity (kg)

REFRIGERANT METERING DEVICE TXV
OUTDOOR COIL

Rows...Fins/in.
Face Ar ea (sq ft)

OUTDOOR FAN

Nominal Cfm
Diameter in.
Diameter (mm)

Motor Hp (Rpm)

INDOOR COIL

Rows...Fins/in.
Face Ar ea (sq ft)

INDOOR BLOWER

Nominal Cooling Airflow (Cfm)

Size in.
Size (mm.)
Motor HP (RPM)

HIGH --- PRESSURE SWITCH
(psig) Cut --- out Reset (Auto)

L O S S --- O F --- C H A R G E / L O W --- P R E S ­SURE SWITCH (Liquid Line) (psig)
cut--- out Reset (auto)

RETURN--- AIR FILTERS†}

Throwaway Si ze in.
Throwaway Si ze (mm)

*For 460 volt units add 14 lb (6.35 kg) to the shipping weight.
{ Required filter sizes shown are based on the larger of the AHRI (Air Conditioning Heating and Refrigeration Institute) rated cooling airflow or the heating air-

flow velocity of 300 ft/minute for throwaway type or 450 ft/minute for high---capacity type. Air filter pressure drop for non ---standard filters must not exceed 0.08
in. W.C.
} If using accessory filter rack refer to the filter rack installation instructions
for correct filter sizes and quantity.

295
134

6.0

2.7

1...21

11.9

2500

24

609.6

1/10 (810)

3...17

3.7

800

10x10

254x254

1/2 (1050)

20x20x1

508x508x25

307
139

5.6

2.5

1...21

13.6

2700

24

609.6

1/10 (810)

3...17

3.7

1000

10x10

254x254

1/2 (1050)

20x24x1

508x610x25

365
166

9.5

4.3

2...21

15.4

2800

24

609.6

1/5 (810)

3...17

3.7

1200

11x10

279.4x254
3/4 (1000)

610x762x25

Scroll

1

1/5 (810)

279.4x254
3/4 (1075)

650 +/ --- 15
420 +/ --- 25

2 0 + / --- 5

45 +/ --- 10

24x30x1

421
191

8.8

4.0

2...21

13.6

3000

26

660.4

3...17

4.7

1400

11x10

439
199

9.4

4.3

2...21

17.5

3200

26

660.4

1/5 (810)

3...17

4.7

1600 1750

11x10

279.4x254

1.0 ( 1075) 1.0 (1040)

24x36x1

610x914x25

467
212

12.5

5.7

2...21

21.4

3600

26

660.4

1/5 (810)

3...17

5.7

11x10

279.4x254

50VL -- A

Table 2 – Minimum Airflow for Safe Electric Heater Operation (CFM)

SIZE 24 30 36 42 48 60

Cfm 800 1000 1200 1400 1600 1750

11

PRE--START--UP

!

WARNING

ENVIRONMENTAL, FIRE, EXPLOSION,
ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal
injury or death and/or property damage.

1. Follow recognized safety practices and wear protective
goggles when checking or servicing refrigerant system.

2. Relieve and recover all refrigerant from system before
touching or disturbing compressor plug if refrigerant
leak is suspected around compressor terminals.

3. Never attempt to repair soldered connection while
refrigerant system is under pressure.

4. Do not use torch to remove any component. System
contains oil and refrigerant under pressure.

5. To remove a component, wear protective goggles and

50VL -- A

proceed as follows:

a. Shut off electrical power to unit and install

lockout tag.

b. Relieve and reclaim all refrigerant from system

using both high-- and low--pressure ports.

c. Cut component connecting 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.

Proceed as follows to inspect and prepare the unit for initial
start--up:

1. Remove all access panels (see Fig. 17).

2. Read and follow instructions on all DANGER, 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, disconnected wires, etc.

b. Inspect for oil at all refrigerant tubing connections and

on unit base. Detecting oil generally indicates a
refrigerant leak. Leak test all refrigerant tubing
connections using electronic leak detector, or
liquid--soap solution. If a refrigerant leak is detected, see
following Check for Refrigerant Leaks section.

c. Inspect all field-- and factory--wiring connections. Be

sure that connections are completed and tight.

d. Ensure wires do not touch refrigerant tubing or sharp

sheet metal edges.

e. Inspect coil fins. If damaged during shipping and

handling, carefully straighten fins with a fin comb.

4. Verify the following conditions:

a. Make sure that condensate drain pan and trap are filled

with water to ensure proper drainage.

b. Make sure that all tools and miscellaneous loose parts

have been removed.

START--UP

Step 1 — Check for Refrigerant Leaks

Proceed as follows to locate and repair a refrigerant leak and to
charge the unit:

1. Locate leak and make sure that refrigerant system pressure
has been relieved and reclaimed from both high-- and
low--pressure ports.

2. Repair leak following accepted practices.

NOTE: Install a filter drier whenever the system has been opened
for repair.

3. Add a small charge of Puron (R--410A) refrigerant vapor to
system and leak--test unit.

4. Recover refrigerant from system and evacuate to 500
microns if no additional leaks are found.

5. Charge unit with Puron (R--410A) refrigerant, using an
accurate scale. Refer to unit rating plate for required charge.

Step 2 — Start--Up Cooling Section And Make
Adjustments

Complete the required procedures given in the Pre--Start--Up
section before starting the unit. Do not jumper any safety devices
when operating the unit. Do not operate the unit when the outdoor
temperature is below 40°F(4°C) (unless accessory low--ambient
kit is installed). Do not rapid cycle the compressor. Allow 5
minutes between “on” cycles to prevent compressor damage.

CHECKING COOLING CONTROL OPERATION

Start and check the unit for proper cooling control operation as
follows:

1. Place room thermostat SYSTEM switch in OFF position.
Observe that blower motor starts when FAN switch is
placed in ON position and shuts down when FAN switch is
placed in AUTO position.

2. Place SYSTEM switch in COOL position and FAN switch
in AUTO position. Set cooling control below room
temperature. Observe that compressor, condenser fan, and
evaporator blower motors start. Observe that compressor
and outdoor fan shut down when control setting is satisfied
and that indoor blower shuts down after 90 second fan time
delay expires.

IMPORTANT: Three--phase, scroll compressors are direction
oriented. Unit must be checked to ensure proper compressor
3--phase power lead orientation. If not corrected within 5 minutes,
the internal protector will shut off the compressor. The 3--phase
power leads to the unit must be reversed to correct rotation. When
turning backwards, the difference between compressor suction and
discharge pressures may be minimal.

CHECKING AND ADJUSTING REFRIGERANT
CHARGE

The refrigerant system is fully charged with Puron (R--410A)
refrigerant and is tested and factory sealed.

NOTE: Adjustment of the refrigerant charge is not required
unless the unit is suspected of not having the proper Puron
(R--410A) charge.

A subcooling charging chart is attached to the inside of the
compressor access panel (see Fig. 17). The chart includes the
required liquid line temperature at given discharge line pressures
and outdoor ambient temperatures.

An accurate thermocouple-- or thermistor-- type thermometer, and a
gauge manifold are required when using the subcooling charging
method for evaluating the unit charge. Do not use mercury or small
dial-- type thermometers because they are not adequate for this type
of measurement.

NOTE: Allow system to operate for a minimum of 15 minutes
before checking or adjusting refrigerant charge.

IMPORTANT: When evaluating the refrigerant charge, an
indicated adjustment to the specified factory charge must always be
very minimal. If a substantial adjustment is indicated, an abnormal
condition exists somewhere in the cooling system, such as
insufficient airflow across either coil or both coils.

12

Proceed as follows:

1. Remove caps from low-- and high--pressure service fittings.

2. Using hoses with valve core depressors, attach low-- and
high--pressure gauge hoses to low-- and high--pressure
service fittings, respectively.

3. Start unit and let run until system pressures stabilize.

4. Measure and record the following:

a. Outdoor ambient--air temperature (°F[°C] db).

b. Liquid line temperature (°F[°C]) at TXV.

c. Discharge (high--side) pressure (psig).

d. Suction (low--side) pressure (psig) (for reference only).

5. Using Cooling Charging Charts compare outdoor--air
temperature (°F[°C] db) with the discharge line pressure
(psig) to determine desired system operating liquid line
temperature (See Fig. 15).

6. Compare actual liquid line temperature with desired liquid
line temperature. Using a tolerance of ±2°F(±1.1°C), add
refrigerant if actual temperature is more than 2°F(1.1°C)
higher than proper liquid line temperature, or remove
refrigerant if actual temperature is more than 2°F(1.1°C)
lower than required liquid line temperature.

NOTE: If the problem causing the inaccurate readings is a
refrigerant leak, refer to Check for Refrigerant Leaks section.

INDOOR AIRFLOW AND AIRFLOW ADJUST­MENTS

!

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in unit damage.

For cooling operation, the recommended airflow is 350 to
450 cfm for each 12,000 Btuh of rated cooling capacity. For
heating operation, the airflow must produce a temperature
rise that falls within the range stamped on the unit rating
plate.

NOTE: Be sure that all supply--and return--air grilles are open,
free from obstructions, and adjusted properly.

!

WARNING

ELECTRICAL SHOCK HAZARD

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

Disconnect electrical power to the unit and install lockout
tag before changing blower speed.

This unit is factory-set up for use with a single cooling fan speed.
In addition, this unit has the field-selectable capability to run two
different cooling fan speeds: The rated cooling fan speed (350~400
CFM/Ton) and an enhanced dehumidification fan speed (As low as
320 CFM/Ton) for use with either a dehumidistat or a thermostat
that supports dehumidification.

The cooling speed is marked “LOW” on the interface fan board
(IFB) (See Fig. 11) . The factory-shipped settings are noted in
Table 4. There are 4 additional speed tap wires available for use in
either electric heating or cooling (For color coding on the indoor
fan motor leads, see Table 3). The additional 4 speed tap wires are

shipped loose with vinyl caps and are located in the control box,
near the interface fan board (IFB) (See Fig. 11).

SINGLE COOLING FAN SPEED SET--UP (Dehumidi­fication feature not

To change cooling speed:

1. Remove the vinyl cap off of the desired speed tap wire
(Refer to Table 3 for color coding). Add the wet coil
pressure drop in Table 6 to the system static to determine the
correct cooling airflow speed in Table 4 that will deliver the
nominal cooling airflow as listed in Table 1 for each size.

2. Remove the current speed tap wire from the “LOW”
terminal on the interface fan board (IFB) (See Fig. 11) and
place vinyl cap over the connector on the wire.

3. Connect the desired speed tap wire to the “LOW” terminal
on the interface fan board (IFB).

NOTE: If accessory electric heat is installed, and the electric heat
fan speed is chosen to be the same as the normal cooling fan speed,
the dry airflow must meet or exceed the minimum airflow speed
specified in Table 2 for the specific size unit.

used)

TWO COOLING FAN SPEEDS SET--UP (Dehumidi­fication feature

IMPORTANT: Dehumidification control must open control

circuit on humidity rise above set point.

Use of the dehumidification cooling fan speed requires use of
either a 24 V AC dehumidistat or a thermostat which includes
control of a 24 VAC dehumidistat connection. In either case, the
dehumidification control must open the control circuit on humidity
rise above the dehumidification set point.

1. Using Fig. 11, move the two pin DEHUM jumper from the
“STD” position to the “DEHUM” position.

2. Remove fan speed tap wire from the “LOW” terminal on
the interface fan board (IFB) (See Fig. 11).

3. Determine correct normal cooling fan speed for unit and
application. Add the wet coil pressure drop in Table 6 to
the system static to determine the correct cooling airflow
speed in Table 4 that will deliver the nominal cooling
airflow as listed in Table 1 for each size.

NOTE: If accessory electric heat is installed, the dry
airflow must meet or exceed the minimum airflow speed
specified in Table 2 for the specific size unit. The electric
heat fan speed will be the same as the normal cooling fan
speed.

4. Remove the vinyl cap off of the desired speed tap wire
(Refer to Table 3 for color coding) for the normal cooling
fan speed and place desired speed tap wire on “HIGH” on
the interface board.

5. Refer to airflow tables (Table 4) to determine allowable
speeds for the dehumidification cooling fan speed. In T able
4, speeds that are not allowed for dehumidification cooling
are shaded.

6. Remove the vinyl cap off of the desired speed tap wire
(Refer to Table 3 for color coding) for the dehumidification
cooling fan speed and place desired speed tap wire on the
“LOW” connection on the interface board (IFB). V erify
that static pressure is in the acceptable range for the speed
tap to be used for dehumidification cooling.

7. Use any spare vinyl plugs to cap any unused speed tap
wires.

used)

50VL -- A

13

HIGH LOW COM

QC5

07 09 080L0

C9

QIL Z2 06 04

D5 D3

P3

SDL

R2

50VL -- A

SSTZ-8

ALO

C4

C7

JW5

QCB

Y

STD

KZ

R13 C8 R11 Q1

A7 R9 AB A15

R3 R5 R6

P1

QC4

DEHUM

U1

P2 JW3

R W2 Y C W3W3W2 W2C

Y2 Y1

W2W3

QC3

KL

D2

Q3

RL

G1

G2

Z1

C3

JWZ

JW4

GCR

YDH

DCR QCR

C

QC1

AL2

01

C0

R4 RL4

Fig. 11 -- Interface Fan Board (IFB)

SINGLE SPEED COOLING WITH HIGHER
ELECTRIC HEAT

This unit can also be configured to operate with single speed
cooling and a higher speed for an accessory electric heater.

1. Using Fig. 11, move the two pin DEHUM jumper from the
“STD” position to the “DEHUM” position.

2. See Table 2 for minimum airflow for electric heat operation.
Add electric heater and filter pressure drop to duct system
static pressure to determine total external static pressure.

3. Select speed tap from Table 4 that will achieve required
airflow from Table 2.

4. Remove the vinyl cap off of the desired speed tap wire
(Refer to Table 3 for color coding).

5. Connect the desired speed tap wire to the “HIGH” terminal
on the interface fan board (IFB).

!

UNIT OPERATION HAZARD

Failure to follow this caution may result in unit component
damage or improper operation.

To use this mode, a speed connection must be made on the
“HIGH” terminal that meets or exceeds the minimum
airflow found in Table 2.

SPEED

CAUTION

F1

P4

24VAC/R3AMP CDM/C

A09059

Table 3 – Color Coding for Indoor Fan Motor Leads

Black = High Speed

Orange = Med--High Speed

Red = Med Speed

Pink = Med--Low Speed

Blue = Low Speed

!

WARNING

ELECTRICAL SHOCK HAZARD

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

Disconnect electrical power to the unit and install lockout
tag before changing blower speed.

CONTINUOUS FAN OPERATION

When the DEHUM feature is not used, the continuous fan speed
will be the same as cooling fan speed. When the DEHUM feature
is used, the continuous fan will operate on IFB “LOW” speed
when the DH control lead is not energized, or IFB “HIGH” speed
when the DH lead is energized (see Fig. 11).

COOLING SEQUENCE OF OPERATION

With the room thermostat SYSTEM switch in the COOL position
and the FAN switch in the AUTO position, the cooling sequence of
operation is as follows:

When the room temperature rises to a point that is slightly above
the cooling control setting of the thermostat, the thermostat
completes the circuit between thermostat terminal R to terminals Y
and G. These completed circuits through the thermostat connect
contactor coil (C) (through unit wire Y) and time delay relay
(TDR) (through unit wire G) across the 24-- V secondary of
transformer (TRAN).

The normally open contacts of energized contactor (C) close and
complete the circuit through compressor motor (COMP) to
condenser (outdoor) fan motor (OFM). Both motors start instantly.

A set of normally open contacts on the interface fan board (IFB)
are closed which energizes a circuit to the indoor fan motor (IFB).

NOTE: Once the compressor has started and then has stopped, it
should not be started again until 5 minutes have elapsed.

The cooling cycle remains on until the room temperature drops to a
point that is slightly below the cooling control setting of the room
thermostat. At this point, the thermostat breaks the circuit between
thermostat terminal R to terminals Y and G. These open circuits
deenergize contactor coil C and IFB. The condenser and
compressor motors stop. After a 90--second delay, the blower
motor stops. The unit is in a standby condition, waiting for the next
call for cooling from the room thermostat.

14

Table 4 – Dry Coil Air Delivery* -- Horizontal Discharge -- Unit 50VL--A24 --60

50VL -- A

EXTERNAL STATIC PRESSURE (IN. W.C.)

EXTERNAL STATIC PRESSURE (IN W.C.)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Table 5 – Dry Coil Air Delivery -- Downflow Discharge

Red CFM 941 851 774 684 576 479 --- --- ---

Orange CFM 1140 1064 996 915 840 758 687 564 480

Red CFM 1354 1290 1226 1158 1102 1046 981 918 843

Orange CFM 1545 1492 1449 1411 1362 1313 1278 1231 1188

Red CFM 1736 1695 1642 1601 1553 1512 1465 1427 1381

Red CFM 1962 1915 1880 1843 1794 1753 1711 1675 1628

High Black CFM 1241 1167 1111 1036 969 881 818 731 640

1

Low Blue CFM 741 638 547 415 --- --- --- --- ---

Medium Red CFM 1088 1023 954 881 800 723 658 563 461

Med-Low Pink CFM 973 887 823 733 665 538 451 --- ---

1

Low Blue CFM 1234 1168 1093 1021 961 894 825 759 687

High Black CFM 1202 1140 1082 1015 961 881 810 732 631

Medium

Med-Low Pink CFM 1290 1223 1154 1090 1027 977 894 828 762

Med-High

Med-High Orange CFM 1606 1546 1489 1430 1371 1316 1258 1208 1140

1

Low Blue CFM 754 650 538 429 --- --- --- --- ---

Medium

Med-Low Pink CFM 851 777 675 591 475 --- --- --- ---

Med-High Orange CFM 1009 917 840 759 667 577 447 --- ---

High Black CFM 1630 1580 1517 1463 1407 1339 1277 1210 1131

Low Blue CFM 1295 1234 1182 1126 1075 1016 955 898 857

Med-Low Pink CFM 1345 1282 1235 1194 1140 1095 1027 974 921

1

Medium Red CFM 1505 1452 1413 1358 1323 1282 1234 1169 1130

1

Low Blue CFM 1402 1351 1311 1263 1224 1172 1136 1080 1041

High Black CFM 1705 1643 1607 1568 1518 1483 1448 1404 1360

Med-Low Pink CFM 1457 1404 1367 1318 1284 1233 1197 1144 1104

Med-High

1

High Black CFM 2344 2306 2259 2203 2141 2070 1991 1902 1803

Med-Low Pink CFM 1678 1635 1602 1558 1513 1474 1438 1404 1349

High Black CFM 2461 2409 2339 2286 2192 2140 2062 1968 1874

Medium

Med-High Orange CFM 2131 2088 2065 2013 1982 1941 1888 1860 1785

Medium

Med-High Orange CFM 2149 2111 2062 2026 1980 1945 1905 1864 1793

MOTOR SPEED WIRE COLOR

UNIT MOTOR SPEED WIRE COLOR

50VL-A24

50VL-A30

50VL-A36

50VL-A42

50VL-A48

50VL-A60

Factory--- shipped cooling speed

Note: Deduct field- -- supplied air filter pressure drop and wet coil pressure drop to obtain external static pressure available for ducting.

Shaded areas indicate speed/static combinations that are not permitted for dehumidification speed.

* Air delivery valu es are without air filter and are for dry coil (See Table 6 --- 50VL --- A Wet Coil Pressure Drop table).

Note: Deduct 10% for 208 volt operation.

1

UNIT

50VL---A24 High Black 1050 1000 950 900 850 - - - - -

50VL---A30 High Black 1050 1000 950 900 850 - - - - -

50VL---A36 High Black 1615 1555 1495 1435 1375 1320 1260 1200 1140 -

50VL---A42 High Black 1775 1710 1670 1630 1580 1540 1505 1460 1415 -

50VL---A48 High Black 2505 2440 2345 2295 2215 2120 2040 1990 1750 -

50VL---A60 High Black 2530 2445 2380 2325 2250 2155 2080 1965 1880 -

15

50VL -- A

STANDARD CFM (SCFM)

STANDARD CFM (SCFM)

STANDARD CFM (SCFM)

STANDARD CFM (SCFM)

Small Cabinet: 24 --36

STANDARD CFM (SCFM)

Large Cabinet: 42--60

Table 9 – Electric Heat Pressure Drop T ables (IN. W.C.)

Table 8 – Horizontal and Downflow Filter Pressure Drop Table (IN. W.C.)

600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200

Table 6 – 50VL--A Horizontal and Downflow Discharge Wet Coil Pressure Drop (IN. W.C.)

600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200

24 0.030 0.037 0.044 0.053 0.063 - - - - - - - - - - - -

30 - - - 0.053 0.063 0.072 0.081 0.105 - - - - - - - - -

36 - - - 0.055 0.060 0.090 0.100 0.110 0.140 - - - - - - - -

42 - - - - 0.045 0.050 0.060 0.065 0.075 0.080 0.090 0.094 0.110 - - - -

SIZE

UNIT

48 - - - - - - 0.041 0.063 0.085 0.100 0.104 0.110 0.120 0.130 0.140 - -

Table 7 – Horizontal and Downflow Economizer with 1--in. Filter Pressure Drop (IN. W.C.)

60 - - - - - - - - - 0.060 0.065 0.007 0.077 0.085 0.100 0.115 0.125

0.07 0.08 0.10 0.14 0.17 0.21 0.25 0.31 0.35 - - - - - - - -

3.0

TONS

COOLING

DOWNFLOW

ECONOMIZER +

INCLUDED FILTERS

5.0 - - - - - - - - - 0.10 0.12 0.13 0.15 0.17 0.18 0.20 0.23

3.5, 4.0 - - - - - - 0.10 0.12 0.13 0.15 0.17 0.19 0.22 - - - -

2.0, 2.5,

600-1400 cfm

1200-1800 cfm

1500-2200 cfm

(12x20x1+12x20x1)

(16x24x1+14x24x1)

(16x24x1+18x24x1)

600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200

TONS

COOLING

(mm)

FILTER SIZE in.

2.0,

600-1400 cfm

0.05 0.07 0.08 0.09 0.10 0.11 0.13 0.14 0.15 - - - - - - - -

2.5,

- - - - - - 0.07 0.08 0.09 0.10 0.11 0.11 0.12 - - - -

3.0

3.5,

1200-1800 cfm

(12x20x1+12x20x1)

5.0 - - - - - - - - - 0.08 0.10 0.10 0.11 0.12 0.13 0.14 0.15

4.0

1500-2200 cfm

(16x24x1+14x24x1)

(16x24x1+18x24x1)

STATIC

500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600

5kW 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.06 0.07

1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500

10 kW 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.06 0.07 0.09 0.10 0.11

15 kW 0.00 0.00 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18

20 kW 0.00 0.00 0.02 0.04 0.06 0.08 0.09 0.11 0.13 0.15 0.17 0.19

5kW 0.00 0.00 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.1 1 0.12

10 kW 0.00 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13

15 kW 0.00 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15

STATIC

20 kW 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15 0.16

16

50VL -- A

Fig. 12 -- Connection Wiring Diagram 208/230--1-- 60

17

A11004

50VL -- A

Fig. 12 Cont. -- Ladder Wiring Diagram 208/230--1--6 0

18

A11003

50VL -- A

Fig. 13 -- Connection Wiring Diagram 208/230--3-- 60

19

A11010

50VL -- A

Fig. 13 Cont. -- Ladder Wiring Diagram 208/230--3--6 0

20

A11009

CONNECTION WIRING DIAGRAM

DANGER: ELECTRICAL SHOCK HAZARD DISCONNECT POWER BEFORE SERVICING

BLK

C

11 21

13 23

YEL

460

24

IF USED

RED

BLU

BLK

RED

C

1423

AUTOTRANSFORMER

TRAN

BLK

FU1 5 AMP

FU2 5 AMP

YEL

C

460

24

BRN

460V

FOR WIRING WITH
ELECTRIC HEATERS
SEE SCHEMATIC
ON HEATER
ACCESSORY.

2435

1

COMPRESSOR PLUG

L2

GND

L1

COM

BRN

OFM

COMP

BLK

YEL

BLK

230V

SEE NOTE 8

RED

BLK

YEL

BLK

CAP

GND

GRN/YEL

YEL

BRN

T1

T3

YEL

T2

BLU

GRN-YEL

SEE NOTE 5 & 6

BRN

RED

BLU

YEL

FIELD

SUPPLY

POWER

UNIT ONLY
MAXIMUM WIRE
SIZE 2 AWG.

ECON
PLUG

7 7

6 6

11 11

10 10

8 8

2 2

3 3

4 4

1 1

5 5

9 9

12 12

L1

EQUIP_GND

CCH

GRN

BLK

1

BLK

1

L3

YEL

1

L2

BLK

ECON

PNK

BLU

SAT

BLU

PNK

GRY

RED

BRN

YEL

BLK

SCHEMATIC

460-3-60

IFM

BLU

PNK

SEE NOTE 4

50VL -- A

RED

ORN

BLK

TSTAT

GRY

Y2

SEE NOTE 7

RED

R

BRN

C

YEL

Y1

GRN

G

DH

BLU

W2

WHT

VIO

W3

UNIT COMPONENT ARRANGEMENT

OUTDOOR FAN
SECTION

COMPRESSOR
SECTION

INDOOR FAN
SECTION

LPS

HPS

CAP

CF

H

COMP

C

S

CCH

R

SEE NOTE 9

R

C

COM

24VAC

3A

FUSE

P1

C

R

OFM

IFM

LOW

COM

COM

54321

6

7

G

W3

W2

Y1/Y

Y2/DH

CONTROL BOX AREA

SINGLE PT.
CONNECTION
FOR
ELECT.HEAT

SEE HEATER
SCHEMATIC
FOR WIRING

STD

P2

21

TRAN

24V SPLICE

IFB

123

C

IFB

BOX

Y

C

HIGH

DEHUM

4

R

W2

11

1323

Y

EQUIP.
GND

24V POWER ENTRY

12435

P4

C

W2

DISCONNECT
PER NEC

ACCESSSORY ELECTRIC HEAT

1

WHT

1

VIO

1

PNK

1

GRY

1

BLK

COLOR CODE

BLK BLACK
BLU BLUE
BRN BROWN
GRY GRAY
GRN GREEN
ORN ORANGE
PNK PINK
RED RED
VIO VIOLET
WHT WHITE

YEL YELLOW

BRN

HPS

BLK

NOTES:

1. IF ANY OF THE ORIGINAL WIRES FURNISHED ARE REPLACED,
IT MUST BE REPLACED WITH TYPE 90 DEGREE C WIRE OR
IT'S EQUIVALENT.

2. SEE PRICE PAGES FOR THERMOSTAT AND SUBBASES.

3. USE 75 DEGREE COPPER CONDUCTORS FOR FIELD INSTALLATION.

4. REFER TO INSTALLATION INSTRUCTIONS
FOR CORRECT SPEED SELECTION OF IFM.

5. RELOCATION OF SPEED TAPS MAY BE REQUIRED
WHEN USING FIELD INSTALLED ELECTRIC HEATERS,
CONSULT INSTALLATION INSTRUCTIONS TO
DETERMINE CORRECT SPEED TAP SETTING.

6. "DO NOT DISCONNECT PLUG UNDER LOAD."

7. THIS FUSE IS MANUFACTURED BY LITTELFUSE, P/N 257003

8. THESE FUSES ARE MANUFACTURED BY COOPER BUSSMAN, P/N FNQ-R-5

9. DEHUM FEATURE CANNOT BE USED WHEN ECONOMIZER IS INSTALLED.
UNIT FACTORY-SHIPPED IN STD MODE.

W3

W2

W3

HR1 (5 KW)

WHT

VIO

HR1,2,3

PNK

HR1 & 2 (10 KW)

GRY

HR1,2 & 3 (15 KW)

BRN

BLU

LEGEND

FIELD SPLICE

TERMINAL (MARKED)

TERMINAL (UNMARKED)

SPLICE (IF USED)
SPLICE (MARKED)

FACTORY WIRING

FIELD CONTROL WIRING

FIELD POWER WIRING
ACCESSORY OR OPTIONAL
WIRING

TO INDICATE COMMON
POTENTIAL ONLY:
NOT TO REPRESENT WIRING

& 4 (20 KW)

LPS

HR1

1

1

HR4

HR2

HR3

BLU

C CONTACTOR
CAP CAPACITOR
CCH CRANK CASE HEATER

ENERGIZED

COMP COMPRESSOR MOTOR
DH DEHUMIDIFICATION MODE
DEHUM DEHUMIDIFICATION MODE
ECON ECONOMIZER
GND GROUND
HPS HIGH PRESSURE SWITCH
HR HEATER RELAY
IFB INTERFACE FAN BOARD
IFM INDOOR FAN MOTOR
LPS LOW PRESSURE SWITCH
OFM OUTDOOR FAN MOTOR
STD STANDARD MODE
TRAN TRANSFORMER

BRN

3

BRN

BRN

3

BRN

BRN

C

C2

C1

A10204C

Fig. 14 -- Connection Wiring Diagram 460--3 --60

21

LADDER WIRING DIAGRAM

DANGER: ELECTRICAL SHOCK HAZARD DISCONNECT POWER BEFORE SERVICING

YEL

L3

YEL

13

13

L1

L2

BLK

11

11

11

50VL -- A

BLK

BLK

IF USED

21

RED

BLK

BLK

BLU

BLK

C

G/Y

CCH

OFM

C

BRN

CAP

T1

COMP

G

L

N

X

GRN

R

S

YEL

YEL

YEL

T2

T3

G/Y

C

23

IFM

460V

TRAN

460V

SEE NOTE 7

R
C

Y1
G

DH

W2

W3

Y2

RED

BRN
YEL

GRN

BLU

WHT

VIO

VIO

G/Y

C

24V

BRN

BRN

BRN

YEL

C1

BRN

C2

C

BRN

BLK

RED

24VAC

RED

IFB

FUSE
3A

P1-1

"R"

P1-2

"C"

P1-3

"Y1/Y"

P1-4

"G"

P1-5

"Y2/DH"

P1-6

"W2"

P1-7

"W3"

P2-1
P2-2
P2-3
P2-4

Y

ACCESSORY

ELECTRIC HEAT

P4-1

P4-2

P4-3

YEL

P4-4

P4-5

LOW

STD

DEHUM

HIGH

WHT

VIO

PNK

GRY

BRN

SEE NOTE 9

SEE NOTE 4

BLK

WHT

VIO

PNK

GRY

HPS

BRN

PNK
RED

BLK

BLK

BLU

ORN

HR1

HR4

HR2

HR3

BLU

24V

LPS

BLU

1
2

IFM

3
4

5

13

C,TRAN

BRN

ECON

HARNESS

2

3
4

5

6

7

8

BRN

PNK

PNK

COM C

BLU

BLU

BLK

SAT

G/Y

C

RED

BRN

50VL500271

D

A10204

Fig. 14 Cont. -- Ladder Wiring Diagram 460--3 -- 60

22

50VL -- A

Fig. 15 -- Cooling Charging Chart

23

A09089

MAINTENANCE

To ensure continuing high performance, and to minimize the
possibility of premature equipment failure, periodic maintenance
must be performed on this equipment. This cooling unit should be
inspected at least once each year by a qualified service person. To
troubleshoot unit, refer to Table 8, Troubleshooting Chart.

NOTE TO EQUIPMENT OWNER: Consult your local dealer
about the availability of a maintenance contract.

!

WARNING

PERSONAL INJURY AND UNIT DAMAGE
HAZARD

Failure to follow this warning could result in personal
injury or death and possible unit component damage.

The ability to properly perform maintenance on this
equipment requires certain expertise, mechanical skills,
tools and equipment. If you do not possess these, do not

50VL -- A

attempt to perform any maintenance on this equipment,
other than those procedures recommended in the Owner’s
Manual.

!

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow these warnings could result in personal
injury or death:

1. Turn off electrical power to the unit and install lockout
tag before performing any maintenance or service on this
unit.

2. Use extreme caution when removing panels and parts.

3. Never place anything combustible either on or in contact
with the unit.

!

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in equipment
damage or improper operation.

Errors made when reconnecting wires may cause improper
and dangerous operation. Label all wires prior to
disconnecting when servicing.

The minimum maintenance requirements for this equipment are as
follows:

1. Inspect air filter(s) each month. Clean or replace when
necessary.

2. Inspect indoor coil, drain pan, and condensate drain each
cooling season for cleanliness. Clean when necessary.

3. Inspect blower motor and wheel for cleanliness each
cooling season. Clean when necessary.

4. Check electrical connections for tightness and controls for
proper operation each cooling season. Service when
necessary.

5. Ensure electric wires are not in contact with refrigerant
tubing or sharp metal edges.

Air Filter

IMPORTANT: Never operate the unit without a suitable air filter

in the return--air duct system. Always replace the filter with the
same dimensional size and type as originally installed. See T able 1
for recommended filter sizes.

Inspect air filter(s) at least once each month and replace
(throwaway--type) or clean (cleanable--type) at least twice during
each cooling season and twice during the heating season, or
whenever the filter becomes clogged with dust and lint.

Indoor Blower and Motor

NOTE: All motors are pre-- lubricated. Do not attempt to lubricate

these motors.

For longer life, operating economy, and continuing efficiency,
clean accumulated dirt and grease from the blower wheel and
motor annually.

!

WARNING

ELECTRICAL SHOCK HAZARD

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

Disconnect and tag electrical power to the unit before
cleaning the blower motor and wheel.

To clean the blower motor and wheel:

1. Remove and disassemble blower assembly as follows:

a. Remove blower access panel (see Fig. 17).

b. Disconnect 5 pin plug and 4 pin plug from indoor

blower motor. Remove capacitor if required.

c. On all units remove blower assembly from unit.

Remove screws securing blower to blower partition and
slide assembly out. Be careful not to tear insulation in
blower compartment.

d. Ensure proper reassembly by marking blower wheel and

motor in relation to blower housing before disassembly.

e. Loosen setscrew(s) that secures wheel to motor shaft,

remove screws that secure motor mount brackets to
housing, and slide motor and motor mount out of
housing.

2. Remove and clean blower wheel as follows:
a. Ensure proper reassembly by marking wheel orientation.

b. Lift wheel from housing. When handling and/or

cleaning blower wheel, be sure not to disturb balance
weights (clips) on blower wheel vanes.

c. Remove caked--on dirt from wheel and housing with a

brush. Remove lint and/or dirt accumulations from
wheel and housing with vacuum cleaner, using soft
brush attachment. Remove grease and oil with mild
solvent.

d. Reassemble wheel into housing.

e. Reassemble motor into housing. Be sure setscrews are

tightened on motor shaft flats and not on round part of
shaft. Reinstall blower into unit.

f. Connect 5 pin plug and 4 pin plug to indoor blower

motor. Reinstall capacitor if required.

g. Reinstall blower access panel (see Fig. 17).

3. Restore electrical power to unit. Start unit and check for

proper blower rotation and motor speeds during cooling
cycles.

24

MOTOR

FAN GRILLE

A

MOTOR SHAFT

A08505

MAX DISTANCE BETWEEN TOP OF FAN GRILLE AND BOTTOM OF FAN BLADE

SIZE

24 6.3 160
30 6.3 160
36 7.3 185
42 7.6 193
48 7.6 193
60 7.6 193

IN. MM

Fig. 16 -- Fan Blade Position

air filter(s). If the drain trough is restricted, clear it with a
“plumbers snake” or similar probe device.

OUTDOOR FAN

“A”

50VL -- A

Control
Access
Panel

A09214

Compressor
Access Panel

Blower
Access
Panel

Fig. 17 -- Unit Access Panels

Outdoor Coil, Indoor Coil, and Condensate Drain Pan

Inspect the condenser coil, evaporator coil, and condensate drain
pan at least once each year.

The coils are easily cleaned when dry; therefore, inspect and clean
the coils either before or after each cooling season. Remove all
obstructions, including weeds and shrubs, that interfere with the
airflow through the condenser coil.

Straighten bent fins with a fin comb. If coated with dirt or lint,
clean the coils with a vacuum cleaner, using the soft brush
attachment. Be careful not to bend the fins. If coated with oil or
grease, clean the coils with a mild detergent and water solution.
Rinse coils with clear water, using a garden hose. Be careful not to
splash water on motors, insulation, wiring, or air filter(s). For best
results, spray condenser coil fins from inside to outside the unit. On
units with an outer and inner condenser coil, be sure to clean
between the coils. Be sure to flush all dirt and debris from the unit
base.

Inspect the drain pan and condensate drain line when inspecting
the coils. Clean the drain pan and condensate drain by removing all
foreign matter from the pan. Flush the pan and drain trough with
clear water. Do not splash water on the insulation, motor, wiring, or

!

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in damage to unit
components.

Keep the condenser fan free from all obstructions to ensure
proper cooling operation. Never place articles on top of the
unit.

1. Remove 6 screws holding condenser grille and motor to top

cover.

2. Turn motor/grille assembly upside down on top cover to

expose the fan blade.

3. Inspect the fan blades for cracks or bends.

4. If fan needs to be removed, loosen the setscrew and slide the

fan off the motor shaft.

5. When replacing fan blade, position blade as shown in Fig.

16.

6. Ensure that setscrew engages the flat area on the motor shaft

when tightening

7. Replace grille.

Electrical Controls and Wiring

Inspect and check the electrical controls and wiring annually. Be
sure to turn off the electrical power to the unit.

Remove access panels (see Fig. 17) to locate all the electrical
controls and wiring. Check all electrical connections for tightness.
Tighten all screw connections. If any smoky or burned connections
are noticed, disassemble the connection, clean all the parts, restrip
the wire end and reassemble the connection properly and securely.

After inspecting the electrical controls and wiring, replace the
access panels (see Fig. 17). Start the unit, and observe at least one
complete heating cycle and one complete cooling cycle to ensure
proper operation. If discrepancies are observed in either or both
operating cycles, or if a suspected malfunction has occurred, check

25

each electrical component with the proper electrical
instrumentation. Refer to the unit wiring label when making these
checkouts.

NOTE: Refer to the heating and/or cooling sequence of operation
in this publication as an aid in determining proper control
operation

Refrigerant Circuit

Inspect all refrigerant tubing connections and the unit base for oil
accumulations annually. Detecting oil generally indicates a
refrigerant leak.

!

WARNING

EXPLOSION, SAFETY AND ENVIRONMENTAL
HAZARD

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

This system uses Puron (R--410A) refrigerant which has

50VL -- A

higher operating 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. If you are unsure, consult the equipment
manufacturer.

charge so that pressure gauges read 0 psi (0 Pa). Never open system
without breaking vacuum with dry nitrogen.

High--Pressure Switch

The high--pressure switch is located in the discharge line and
protects against excessive condenser coil pressure. It opens at 650
psig (31.1 kPa). High pressure may be caused by a dirty condenser
coil, failed fan motor, or condenser air recirculation.

To check switch:

1. Turn off all power to unit.

2. Disconnect leads on switch.

3. Apply ohmmeter leads across switch. You should have

continuity on a good switch.

Copeland Scroll Compressor (Puron Refrigerant)

The compressor used in this product is specifically designed to
operate with Puron (R--410A) refrigerant and cannot be
interchanged.

The compressor is an electrical (as well as mechanical) device.
Exercise extreme caution when working near compressors. Power
should be shut off, if possible, for most troubleshooting techniques.
Refrigerants present additional safety hazards.

!

WARNING

If oil is detected or if low cooling performance is suspected,
leak--test all refrigerant tubing using an electronic leak--detector,
halide torch, or liquid--soap solution. If a refrigerant leak is
detected, refer to Check for Refrigerant Leaks section.

If no refrigerant leaks are found and low cooling performance is
suspected, refer to Checking and Adjusting Refrigerant Charge
section.

Evaporator Airflow

The heating and/or cooling air--flow does not require checking
unless improper performance is suspected. If a problem exists, be
sure that all supply-- and return--air grilles are open and free from
obstructions, and that the air filter is clean. When necessary, refer to
Indoor Airflow and Airflow Adjustments section to check the
system airflow.

Puron Items

The indoor metering device is a TXV type device.

Pressure Switches

Pressure switches are protective devices wired into the control
circuit (low voltage). They shut off compressor if abnormally high
or low pressures are present in the refrigeration circuit. These
pressure switches are specifically designed to operate with Puron
(R--410A) systems. R--22 pressure switches must not be used as
replacements for the Puron (R--410A) air conditioner.

Loss of Charge/Low--Pressure Switch (Air Conditioner
Only)

This switch is located on the liquid line and protects against low
suction pressures caused by such events as loss of charge, low
airflow across indoor coil, dirty filters, etc. It opens on a pressure
drop at about 20 psig (957 Pa). If system pressure is above this,
switch should be closed.

To check switch:

1. Turn off all power to unit.

2. Disconnect leads on switch.

3. Apply ohmmeter leads across switch. You should have
continuity on a good switch.

NOTE: Because these switches are attached to refrigeration
system under pressure, it is not advisable to remove this device for
troubleshooting unless you are reasonably certain that a problem
exists. If switch must be removed, remove and recover all system

FIRE/EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury or death and/or property damage.

Wear safety glasses and gloves when handling refrigerants.
Keep torches and other ignition sources away from
refrigerants and oils.

The scroll compressor pumps refrigerant throughout the system by
the interaction of a stationary and an orbiting scroll. The scroll
compressor has no dynamic suction or discharge valves, and it is
more tolerant of stresses caused by debris, liquid slugging, and
flooded starts. The compressor is equipped with a noise reducing
shutdown device and an internal pressure relief port. The pressure
relief port is a safety device, designed to protect against extreme
high pressure. The relief port has an operating range between 550
(26.3 kPa) and 625 (29.9 kPa) psig differential pressure.

Refrigerant

!

WARNING

EXPLOSION, ENVIRONMENTAL HAZARD

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

This system uses Puron (R--410A) refrigerant which has
higher operating 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. If you are unsure, consult the equipment
manufacturer.

This system uses Puron (R--410A) refrigerant which has higher
operating pressures than R --22 and other refrigerants. No other
refrigerant may be used in this system. Gage set, hoses, and
recovery system must be designed to handle Puron. If you are
unsure, consult the equipment manufacturer. Failure to use Puron
compatible servicing equipment or replacement components may
result in property damage or injury.

Compressor Oil

The Copeland scroll compressor uses 3MAF POE oil. If additional
oil is needed, use Uniqema RL32--3MAF . If this oil is not
available, use Copeland Ultra 32 CC or Mobil Arctic EAL22 CC.
This oil is extremely hygroscopic, meaning it absorbs water

26

readily. POE oils can absorb 15 times as much water as other oils
designed for HCFC and CFC refrigerants. Take all necessary
precautions to avoid exposure of the oil to the atmosphere.

Servicing Systems on Roofs with Synthetic Materials

POE (polyolester) compressor lubricants are known to cause long
term damage to some synthetic roofing materials. Exposure, even if
immediately cleaned up, may cause embrittlement (leading to
cracking) to occur in one year or more. When performing any
service that may risk exposure of compressor oil to the roof, take
appropriate precautions to protect roofing. Procedures which risk
oil leakage include, but are not limited to, compressor replacement,
repairing refrigerant leaks, replacing refrigerant components such
as filter drier, pressure switch, metering device, coil, accumulator,
or reversing valve.

Synthetic Roof Precautionary Procedure

1. Cover extended roof working area with an impermeable
polyethylene (plastic) drip cloth or tarp. Cover an
approximate10x10ft (3x3m)area.

2. Cover area in front of the unit service panel with a terry
cloth shop towel to absorb lubricant spills, prevent run--of fs,
and protect drop cloth from tears caused by tools or
components.

3. Place terry cloth shop towel inside unit immediately under
component(s) to be serviced and prevent lubricant run -- offs
through the louvered openings in the unit base.

4. Perform required service.

5. Remove and dispose of any oil contaminated material per
local codes.

Liquid Line Filter Drier

The filter drier is specifically designed to operate with Puron. Use
only factory--authorized components. Filter drier must be replaced
whenever the refrigerant system is opened. When removing a filter
drier, use a tubing cutter to cut the drier from the system. Do not
unsweat a filter drier from the system. Heat from unsweating will
release moisture and contaminants from drier into system.

Puron (R--410A) Refrigerant Charging

Refer to unit information plate and charging chart. Some R--410A
refrigerant cylinders contain a dip tube to allow liquid refrigerant to
flow from cylinder in upright position. For cylinders equipped
with a dip tube, charge Puron units with cylinder in upright
position and a commercial metering device in manifold hose.
Charge refrigerant into suction--line.

TROUBLESHOOTING

Refer to the Troubleshooting Chart (Table 10) for troubleshooting
information.

START--UP CHECKLIST

Use the Start--Up Checklist at the back of this manual.

50VL -- A

27

Table 10 – Troubleshooting Chart

SYMPTOM CAUSE REMEDY

Compressor and outdoor fan will not start

Compressor will not start but condenser fan
runs

Three--phase scroll compressor (size 30-­60 unit) has a low pressure differential 3--phase power leads to the unit

50VL -- A

Compressor cycles (other than normally
satisfying) cooling/heating calls

Compressor operates continuously

Excessive head pressure

Head pressure too low

Excessive suction pressure Refrigerant overcharged Recover excess refrigerant

Suction pressure too low

Power failure Call power company
Fuse blown or circuit breaker tripped Replace fuse or reset circuit breaker
Defective contactor, transformer, control relay, or high--

pressure, loss --of --charge or low--pressure switch
Insufficient line voltage Determine cause and correct
Incorrect or faulty wiring Check wiring diagram and rewire correctl y
Thermostat setting too low/too high Reset thermostat setting
Faulty wiring or circuit
Loose connections in compressor
Compressor motor burned out, seized, or Determine cause
internal overload open Replace compressor
Defective run capacitor, overload, or PTC (positive
temperature coefficient) thermistor

One leg of 3- -phase power dead

Low input voltage Determine cause and correct

Scroll compressor is rotating in the wrong direction

Refrigerant overcharge or undercharge

Defective compressor Replace and determine cause
Insufficient line voltage Determine cause and correct
Blocked outdoor coil Determine cause and correct
Defective run/start capaci tor, overload or start relay Determine cause and replace
Faulty outdoor 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 temperature set too low Reset thermostat setting
Low refrigerant charge Locate leak, repair, and recharge

Air in system

Outdoor coil dirty or restricted Clean coil or remove restriction
Dirty air filter Replace filter
Dirty indoor or outdoor coil Clean coil
Refrigerant overcharged Recover excess refrigerant

Air in system

Indoor or outdoor air restricted or air short--cycling Determine cause and correct
Low refrigerant charge Check for leaks, repair and recharge
Restriction in liquid tube Remove restriction

Dirty air filter Replace filter
Low refrigerant charge Check for leaks, repair and recharge
Metering device or low si de restricted Remove source of restriction
Insufficient coil airflow Check filter–replace if necessary
Temperature too low in conditioned area Reset thermostat setting
Outdoor ambient below 55°F(13°C) Install low--ambient kit
Filter drier restricted Replace

Replace component

Check wiring and repair or replace

Determine cause and replace

Replace fuse or reset circuit breaker
Determine cause

Correct the direction of rotation by reversing the

Recover refrigerant, evacuate system, and re­charge to capacities shown on rating plate

Recover refrigerant, evacuate system, and re­charge

Recover refrigerant, evacuate system, and re­charge

28

AIR CONDITIONER WITH PURON (R--410A) QUICK REFERENCE GUIDE

Puron refrigerant operates at 50--70 percent higher pressures than R--22. Be sure that servicing equipment and replacement components are
designed to operate with Puron. Puron refrigerant cylinders are rose colored.

S Puron refrigerant cylinders manufactured prior to March 1, 1999, have a dip tube that allows liquid to flow out of cylinder in upright

position.

Cylinders manufactured March 1, 1999 and later DO NOT have a dip tube and MUST be positioned upside down to allow liquid to flow.

S Recovery cylinder service pressure rating must be 400 psig. DOT 4BA400 or DOT BW400.
S Puron systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold hose.
S Manifold sets should be minimum 700 psig high--side and 180 psig low--side with 550 psig low--side retard.
S Use hoses with minimum 700 psig service pressure rating.
S Leak detectors should be designed to detect HFC refrigerant.
S Puron, as with other HFCs, is only compatible with POE oils.
S Vacuum pumps will not remove moisture from oil.
S Only use factory specified liquid--line filter driers with rated working pressures no less than 600 psig.
S Do not install a suction--line filter drier in liquid line.
S POE oils absorb moisture rapidly. Do not expose oil to atmosphere.
S POE oils may cause damage to certain plastics and roofing materials.
S Wrap all filter driers and service valves with wet cloth when brazing.
S A Puron liquid-- line filter drier is required on every unit.
S Do not use an R--22 TXV.
S Never open system to atmosphere while it is under a vacuum.
S When system must be opened for service, break vacuum with dry nitrogen and replace filter driers.
S Always replace filter drier after opening system for service.
S Do not vent Puron into the atmosphere.
S Observe all warnings, cautions, and bold text.
S Do not leave Puron suction line driers in place for more than 72 hrs.

50VL -- A

29

START--UP CHECKLIST

(Remove and Store in Job Files)

I. PRELIMINARY INFORMATION

MODEL NO.:

SERIAL NO.:
DATE:

TECHNICIAN:

II. PREST ART--UP (Insert check mark in box as each item is completed)

( ) VERIFY THAT ALL PACKING MATERIALS HAVE BEEN REMOVED FROM UNIT

( ) REMOVE ALL SHIPPING HOLD DOWN BOLTS AND BRACKETS PER INSTALLATION INSTRUCTIONS
( ) CHECK ALL ELECTRICAL CONNECTIONS AND TERMINALS FOR TIGHTNESS
( ) CHECK THAT INDOOR (EVAPORATOR) AIR FILTER IS CLEAN AND IN PLACE

( ) VERIFY THAT UNIT INSTALLATION IS LEVEL
( ) CHECK FAN WHEEL, AND PROPELLER FOR LOCATION IN HOUSING/ORIFICE AND SETSCREW TIGHTNESS

III. START-- UP

50VL -- A

ELECTRICAL

SUPPLY VOLTAGE
COMPRESSOR AMPS

INDOOR (EVAPORATOR) FAN AMPS

TEMPERATURES

OUTDOOR (CONDENSER) AIR TEMPERATURE DB
RETURN--AIR TEMPERATURE DB WB
COOLING SUPPLY AIR DB WB

PRESSURES

REFRIGERANT SUCTION PSIG, SUCTION LINE TEMP*
REFRIGERANT DISCHARGE PSIG, LIQUID TEMP{
( ) VERIFY REFRIGERANT CHARGE USING CHARGING CHARTS

* Measur ed at suction inlet to compressor
{ Measured at liquid line leaving condenser.

Copyright 2011 Carrier Corp. S 7310 W. Morris St. S Indianapolis, IN 46231 Edition Date: 01/11

Manufacturer reserves the ri ght to change, at any time, specifications and designs without notice and without obligations.

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Catalog No:50VL--- 08SI

Replaces: 50VL---07SI