Instruction manual | Carrier 50VL---A Air Conditioner User Manual

50VL---A
Performancet 14 SEER Single ---Packaged Air Conditioner
System with Puron® (R ---410A) Refrigerant
Single and Three Phase
2---5 Nominal Tons (Sizes 24---60)
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--26
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
A09033
Fig. 1 -- Unit 50VL--A
SAFETY CONSIDERATIONS
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.
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 off accessory heater
power switch if applicable.
WARNING
!
50VL-- A
PERSONAL
HAZARD
INJURY
AND
ENVIRONMENTAL
Failure to relieve system pressure could result in personal
injury and/or death.
1. Relieve pressure and recover all refrigerant before
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.
CAUTION
!
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.
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.)
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.
RECEIVING AND INSTALLATION
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.
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.
CAUTION
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.
2
50VL-- A
A09462
Fig. 2 -- 50VL--A24--36 Unit Dimensions
3
50VL-- A
A09463
Fig. 3 -- 50VL--A42--60 Unit Dimensions
4
Dashed lines show cross support
location for large basepan units.
B
G
HVAC unit
basepan
HVAC unit
base rails
C
Sealing
Gasket
Roofcurb
A
Anchor screw
H
F
Wood nailer*
Flashing field
supplied
Roofcurb*
Insulation
(field supplied)
E
D
Cant strip
field supplied
SMALL/COMMON CURB
50VL-- A
Roofing material
field supplied
A09413
*Provided with roofcurb
A09090
ROOF CURB DETAIL
B
C
SUPPLY
AIR
SMALL
BASE
UNIT
RETURN
AIR
LARGE
BASE
UNIT
G
H
F A
E
D
UNIT PLACEMENT ON
COMMON CURB
SMALL OR LARGE BASE UNIT
A09415
LARGE CURB
A09094
A09414
UNIT
SIZE
CATALOG
NUMBER
Small
or
Large
CPRFCURB010A00
Large
CPRFCURB011A00
CPRFCURB012A00
CPRFCURB013A00
A
IN.
(mm)
11
(279)
14
(356)
11
(279)
14
(356)
B
(small/common
base)
IN. (mm)*
B
(large base)
IN. (mm)*
C
IN.
(mm)
D
IN.
(mm)
E
IN.
(mm)
F
IN.
(mm)
32.4
(822)
10 (254)
16
(406)
14 (356)
47.8
(1214)
H
IN. (mm)
30.6 (778)
2.7
(69)
43.9
(1116)
14 (356)
G
IN. (mm)
46.1 (1170)
42.2 (1072)
* Part Numbers CPRCURB010A00 and CPRCURB011A00 can be used on both small and large basepan units. The 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.
Fig. 4 -- Roof Curb Dimensions
5
CAUTION - NOTICE TO RIGGERS
PRUDENCE - AVIS AUX MANIPULATEUR
ACCESS PANELS MUST BE IN PLACE WHEN RIGGING.
PANNEAUX D'ACCES DOIT ÊTRE EN PLACE POUR MANIPULATION.
Use top skid as spreader bar. / Utiliser la palette du haut comme barre de répartition
DUCTS
50VL-- A
MINIMUM HEIGHT: 36" (914.4 mm)
HAUTEUR MINIMUM
SEAL STRIP MUST BE IN
PLACE BEFORE PLACING
UNIT ON ROOF CURB
UNIT HEIGHT
HAUTEUR D'UNITÉ
BANDE SCELLANT DOIT ÊTRE
EN PLACE AVANT DE PLACER
L'UNITÉ SUR LA BASE DE TOIT
DETAIL A
VOIR DÉTAIL A
SEE DETAIL A
VOIR DÉTAIL A
50CY502286 2.0
A09051
Unit*
Rigging
Weight
24
lb
295
SMALL CABINET
30
kg
lb
134
307
36
kg
139
lb
365
Unit*
kg
Rigging
Weight
166
42
lb
421
* For 460 volt units, add 14 lb (6.35 kg) to the rigging weight.
NOTE: See dimensional drawing for corner weighs.
Fig. 5 -- 50VL--A Unit Suggested Rigging
6
LARGE CABINET
48
kg
lb
kg
lb
kg
191
199
467
212
439
60
Step 3 — Provide Clearances
INSPECTION
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.
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.
!
UNIT FALLING HAZARD
Failure to follow this warning could result in personal
injury or death.
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.
!
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)
!
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.
A
WARNING
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.
OPTIONAL
RETURN
AIR
OPENING
C
OPTIONAL
SUPPLY
AIR
OPENING
MAXIMUM ALLOWABLE
DIFFERENCE in. (mm)
B
A-B
B-C
A-C
1/4 (6.35)
1/4 (6.35)
1/4 (6.35)
2˝
(50.8mm)
A07925
Fig. 6 -- Unit Leveling Tolerances
EVAP. COIL
COND. COIL
A07926
Fig. 7 -- Slab Mounting Detail
7
50VL-- A
Never stand beneath rigged units or lift over people.
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.
WARNING
50VL-- A
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.
TRAP
OUTLET
1-in. (25 mm) min.
2-in. (51 mm) min.
A09052
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
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) DISCHARGE
!
WARNING
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.
8
!
CAUTION
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.
Horizontal Duct Covers
A09076
Basepan
Downflow
(Vertical)
Supply
Knockout
Basepan
Downflow
(Vertical)
Return
Knockout
A09093
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.
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.
9
50VL-- A
UNIT COMPONENT DAMAGE HAZARD
SPECIAL PROCEDURES FOR 208-- V OPERATION
HIGH VOLTAGE
POWER LEADS
(SEE UNIT WIRING
LABEL)
3-PHASE SHOWN
1-PHASE USES
TWO POWER
EQUIP GR
LEADS
!
POWER
SUPPLY
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
FIELD-SUPPLIED
FUSED DISCONNECT
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 BOX
WHT(W1)
VIO (W2)
YEL(Y)
50VL-- A
GRN(G)
LOW-VOLTAGE
POWER LEADS
(SEE UNIT
WIRING LABEL)
WARNING
RED(R)
BRN(C)
W1
W2
Y
CONTROL VOLTAGE CONNECTIONS
G
R
THERMOSTAT
(TYPICAL)
C
BLU (DH)
DH
GRA (Y2)
3-Phase
Only
SPLICE BOX
A09066
Fig. 10 -- High-- and Control--Voltage Connections
5. Connect field wire L2 to yellow wire on connection 23 of
the compressor contactor.
Three--phase units:
1. Run the high--voltage (L1, L2, L3) 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.
5. Connect field wire L3 to yellow wire on connection 13 of
the compressor contactor.
6. Connect field wire L2 to blue wire from compressor.
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
24
2
295
134
COMPRESSORS
Quantity
REFRIGERANT (R --- 410A)
Quantity lb
Quantity (kg)
REFRIGERANT METERING DEVICE
OUTDOOR COIL
Rows...Fins/in.
Face Area (sq ft)
OUTDOOR FAN
Nominal Cfm
Diameter in.
Diameter (mm)
Motor Hp (Rpm)
INDOOR COIL
Rows...Fins/in.
Face Area (sq ft)
INDOOR BLOWER
Nominal Cooling Airflow (Cfm)
Size in.
Size (mm.)
Motor HP (RPM)
HIGH --- PRESSURE SWITCH
(psig) Cut--- out Reset (Auto)
LOSS--- OF--- CHARGE / LOW --- PRESSURE SWITCH (Liquid Line) (psig)
cut--- out Reset (auto)
RETURN--- AIR FILTERS†}
Throwaway Size in.
Throwaway Size (mm)
30
2 ---1/2
307
139
36
3
365
166
42
3 ---1/2
421
191
48
4
439
199
60
5
467
212
8.8
4.0
9.4
4.3
12.5
5.7
Scroll
1
6.0
2.7
5.6
2.5
9.5
4.3
TXV
1...21
11.9
1...21
13.6
2...21
15.4
2...21
13.6
2...21
17.5
2...21
21.4
2500
24
609.6
1/10 (810)
2700
24
609.6
1/10 (810)
2800
24
609.6
1/5 (810)
3000
26
660.4
1/5 (810)
3200
26
660.4
1/5 (810)
3600
26
660.4
1/5 (810)
3...17
3.7
3...17
3.7
3...17
3.7
3...17
4.7
3...17
4.7
3...17
5.7
800
10x10
254x254
1/2 (1050)
1000
10x10
254x254
1/2 (1050)
1600
11x10
279.4x254
1.0 (1075)
1750
11x10
279.4x254
1.0 (1040)
1200
1400
11x10
11x10
279.4x254
279.4x254
3/4 (1000)
3/4 (1075)
650 +/ --- 15
420 +/ --- 25
20 +/ --- 5
45 +/ --- 10
20x20x1
508x508x25
20x24x1
508x610x25
24x30x1
610x762x25
24x36x1
610x914x25
*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 airflow 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.
Table 2 – Minimum Airflow for Safe Electric Heater Operation (CFM)
SIZE
Cfm
24
800
30
1000
36
1200
42
1400
11
48
1600
60
1750
50VL-- A
UNIT SIZE
NOMINAL CAPACITY (ton)
SHIPPING WEIGHT* lb.
SHIPPING WEIGHT* (kg)
PRE--START--UP
!
WARNING
50VL-- A
ENVIRONMENTAL,
FIRE,
ELECTRICAL SHOCK HAZARD
EXPLOSION,
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
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
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 used)
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.
TWO COOLING FAN SPEEDS SET-- UP (Dehumidification feature used)
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 VAC 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 Table
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). Verify
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.
13
50VL-- A
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.
QC5
LOW
COM
QC4
QC3
KL
KZ
09 0L0
08
ALO
R13 C8
R11
DCR
D2
QC1
Q3
C4
AL2
RL
G1
Z2
06
04
A7
R9
Failure to follow this warning could result in personal
injury or death.
AB A15
C0
F1
Disconnect electrical power to the unit and install lockout
tag before changing blower speed.
Z1
U1
R4
C3
WARNING
ELECTRICAL SHOCK HAZARD
01
G2
QIL
!
3AMP
C9
QCR
C
Q1
Black = High Speed
Orange = Med--High Speed
Red = Med Speed
Pink = Med--Low Speed
Blue = Low Speed
24VAC/R
07
Table 3 – Color Coding for Indoor Fan Motor Leads
CDM/C
STD
DEHUM
HIGH
RL4
D5 D3
CONTINUOUS FAN OPERATION
JWZ
P3
JW5
R2
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).
R3 R5 R6
P2
QCB
JW3
P4
SDL
50VL-- A
C7
Y
R
W2 Y
C
W3 W3 W2 W2 C
JW4
COOLING SEQUENCE OF OPERATION
SSTZ-8
P1
Y1
W3 W2 Y2
DH G Y
C
R
A09059
Fig. 11 -- Interface Fan Board (IFB)
SINGLE SPEED COOLING WITH HIGHER
ELECTRIC HEAT SPEED
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).
!
CAUTION
UNIT OPERATION HAZARD
Failure to follow this caution may result in unit component
damage or improper 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.
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.
14
15
50VL --- A24
50VL --- A30
50VL --- A36
50VL --- A42
50VL --- A48
50VL --- A60
UNIT
UNIT
MOTOR SPEED
High
High
High
High
High
High
MOTOR SPEED
WIRE COLOR
Black
Black
Black
Black
Black
Black
0.1
1050
1050
1615
1775
2505
2530
0.2
1000
1000
1555
1710
2440
2445
0.3
950
950
1495
1670
2345
2380
50VL-- A
EXTERNAL STATIC PRESSURE (IN W.C.)
0.4
0.5
0.6
0.7
900
850
900
850
1435
1375
1320
1260
1630
1580
1540
1505
2295
2215
2120
2040
2325
2250
2155
2080
Table 5 – Dry Coil Air Delivery -- Downflow Discharge
0.8
1200
1460
1990
1965
EXTERNAL STATIC PRESSURE (IN. W.C.)
WIRE COLOR
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Low
Blue
CFM
754
650
538
429
------Med-Low
Pink
CFM
851
777
675
591
475
----50VL-A24
Medium1
Red
CFM
941
851
774
684
576
479
--Med-High
Orange
CFM
1009
917
840
759
667
577
447
High
Black
CFM
1241
1167
1111
1036
969
881
818
Low
Blue
CFM
741
638
547
415
------Med-Low
Pink
CFM
973
887
823
733
665
538
451
50VL-A30
Medium
Red
CFM
1088
1023
954
881
800
723
658
Med-High1
Orange
CFM
1140
1064
996
915
840
758
687
High
Black
CFM
1202
1140
1082
1015
961
881
810
Low
Blue
CFM
1234
1168
1093
1021
961
894
825
Med-Low
Pink
CFM
1290
1223
1154
1090
1027
977
894
50VL-A36
Medium1
Red
CFM
1354
1290
1226
1158
1102
1046
981
Med-High
Orange
CFM
1606
1546
1489
1430
1371
1316
1258
High
Black
CFM
1630
1580
1517
1463
1407
1339
1277
Low
Blue
CFM
1295
1234
1182
1126
1075
1016
955
Med-Low
Pink
CFM
1345
1282
1235
1194
1140
1095
1027
50VL-A42
Medium
Red
CFM
1505
1452
1413
1358
1323
1282
1234
Med-High1
Orange
CFM
1545
1492
1449
1411
1362
1313
1278
High
Black
CFM
1705
1643
1607
1568
1518
1483
1448
Low
Blue
CFM
1402
1351
1311
1263
1224
1172
1136
Med-Low
Pink
CFM
1457
1404
1367
1318
1284
1233
1197
1
50VL-A48
Medium
Red
CFM
1736
1695
1642
1601
1553
1512
1465
Med-High
Orange
CFM
2149
2111
2062
2026
1980
1945
1905
High
Black
CFM
2344
2306
2259
2203
2141
2070
1991
Med-Low
Pink
CFM
1678
1635
1602
1558
1513
1474
1438
Medium1
Red
CFM
1962
1915
1880
1843
1794
1753
1711
50VL-A60
Med-High
Orange
CFM
2131
2088
2065
2013
1982
1941
1888
High
Black
CFM
2461
2409
2339
2286
2192
2140
2062
* Air delivery values are without air filter and are for dry coil (See Table 6 --- 50VL ---A Wet Coil Pressure Drop table).
1 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.
Note: Deduct 10% for 208 volt operation.
Table 4 – Dry Coil Air Delivery* -- Horizontal Discharge -- Unit 50VL--A24--60
0.9
1140
1415
1750
1880
0.8
--------731
----563
564
732
759
828
918
1208
1210
898
974
1169
1231
1404
1080
1144
1427
1864
1902
1404
1675
1860
1968
1
-
0.9
--------640
----461
480
631
687
762
843
1140
1131
857
921
1130
1188
1360
1041
1104
1381
1793
1803
1349
1628
1785
1874
16
600
0.030
-
5 kW
10 kW
15 kW
20 kW
STATIC
5 kW
10 kW
15 kW
20 kW
STATIC
1100
0.00
0.00
0.00
0.02
-
5.0
1200
0.00
0.00
0.02
0.03
600
0.00
0.00
0.00
0.00
1300
0.00
0.01
0.03
0.04
-
-
0.05
600
-
3.5, 4.0
600
0.07
5.0
1000
0.063
0.063
0.060
0.045
-
1100
0.072
0.090
0.050
-
1200
0.081
0.100
0.060
0.041
-
STANDARD CFM (SCFM)
1300
1400
1500
0.105
0.110
0.140
0.065
0.075
0.080
0.063
0.085
0.100
0.060
1600
0.090
0.104
0.065
1700
0.094
0.110
0.007
1800
0.110
0.120
0.077
-
-
0.10
800
-
-
0.14
900
-
-
0.17
1000
-
-
0.21
1100
-
0.10
0.25
1200
-
0.12
0.31
1300
-
0.13
0.35
1400
0.10
0.15
-
1500
STANDARD CFM (SCFM)
0.12
0.17
-
1600
1400
0.01
0.02
0.04
0.05
700
0.00
0.00
0.00
0.02
-
-
0.07
700
-
-
0.09
900
-
-
0.10
1000
-
-
0.11
1100
-
0.07
0.13
1200
-
0.08
0.14
-
0.09
0.15
0.08
0.10
-
STANDARD CFM (SCFM)
1300
1400
1500
1500
0.02
0.03
0.05
0.06
800
0.00
0.00
0.02
0.04
1600
0.03
0.04
0.06
0.07
STANDARD CFM (SCFM)
1000
1100
0.00
0.00
0.02
0.04
0.06
0.08
0.08
0.09
STANDARD CFM (SCFM)
1700
1800
1900
0.04
0.05
0.06
0.05
0.06
0.07
0.07
0.08
0.09
0.08
0.09
0.10
Large Cabinet: 42--60
900
0.00
0.00
0.04
0.06
2000
0.07
0.08
0.10
0.11
1200
0.00
0.06
0.10
0.11
Table 9 – Electric Heat Pressure Drop Tables (IN. W.C.)
Small Cabinet: 24--36
-
-
0.08
800
0.10
0.11
-
1300
0.02
0.07
0.12
0.13
0.10
0.11
-
1700
0.13
0.19
-
1700
2100
0.08
0.09
0.11
0.12
1600
Table 8 – Horizontal and Downflow Filter Pressure Drop Table (IN. W.C.)
-
-
0.08
700
1900
0.130
0.085
2200
0.09
0.10
0.12
0.13
1400
0.04
0.09
0.14
0.15
0.11
0.12
-
1800
0.15
0.22
-
1800
Table 7 – Horizontal and Downflow Economizer with 1--in. Filter Pressure Drop (IN. W.C.)
900
0.053
0.053
0.055
-
Table 6 – 50VL--A Horizontal and Downflow Discharge Wet Coil Pressure Drop (IN. W.C.)
2.0, 2.5,
3.0
COOLING
TONS
800
0.044
-
COOLING
TONS
2.0,
2.5,
3.0
3.5,
4.0
700
0.037
-
500
0.00
0.00
0.00
0.00
1200-1800 cfm
(16x24x1+14x24x1)
1500-2200 cfm
(16x24x1+18x24x1)
600-1400 cfm
(12x20x1+12x20x1)
FILTER SIZE in.
(mm)
DOWNFLOW
ECONOMIZER +
INCLUDED FILTERS
600-1400 cfm
(12x20x1+12x20x1)
1200-1800 cfm
(16x24x1+14x24x1)
1500-2200 cfm
(16x24x1+18x24x1)
UNIT
SIZE
24
30
36
42
48
60
50VL-- A
2300
0.10
0.11
0.13
0.14
0.12
-
-
1900
0.17
-
-
1900
0.14
-
-
2100
0.20
-
-
2100
2100
0.115
2400
0.11
0.12
0.14
0.15
1500
0.06
0.10
0.16
0.17
0.13
-
-
2000
0.18
-
-
2000
2000
0.140
0.100
2500
0.12
0.13
0.15
0.16
1600
0.07
0.11
0.18
0.19
0.15
-
-
2200
0.23
-
-
2200
2200
0.125
50VL-- A
A11004
Fig. 12 -- Connection Wiring Diagram 208/230--1--60
17
50VL-- A
A11003
Fig. 12 Cont. -- Ladder Wiring Diagram 208/230--1--60
18
50VL-- A
A11010
Fig. 13 -- Connection Wiring Diagram 208/230--3--60
19
50VL-- A
A11009
Fig. 13 Cont. -- Ladder Wiring Diagram 208/230--3--60
20
CONNECTION WIRING DIAGRAM
DANGER: ELECTRICAL SHOCK HAZARD DISCONNECT POWER BEFORE SERVICING
BLK
GRN
L1
UNIT ONLY
MAXIMUM WIRE
SIZE 2 AWG.
C
1
L3
1
BLK
11
21
BLK
YEL
13
23
YEL
OFM
YEL
CAP
BLK
BRN
COMPRESSOR PLUG
T1
L2
BLU
1
EQUIP_GND
FU1 5 AMP
6
11
11
10
10
BLU
BLU
T3
T2
RED
SAT
YEL
YEL
8
YEL
C
460V
1
2
3
L2
GND
GRN-YEL
L1
COM
BLK
BLK
C
COMP
230V
GRN/YEL
IFM
BRN
4
1 2 34 5
8
8
2
2
3
3
4
4
1
1
5
5
9
9
AUTOTRANSFORMER
GRY
SEE NOTE 5
460
460
RED
& 6
BRN
TRAN
24
24
BLK
ORN
BLK
PNK
BRN
BRN
RED
YEL
12
BLU
RED
SEE NOTE
4
GRY
HIGH
9
ACCESSSORY ELECTRIC HEAT
STD
DEHUM
LOW
COM
COM
BRN
R
C
SEE NOTE
7
3A 24VAC
RED
C
SEE NOTE
R
COM
Y2
TSTAT
FUSE
WHT
YEL
W2
WHT
IFB
PNK
P4
1
2
3
4
P2
C
Y
W2
R
BRN
1
HR1,2,3
PNK
LPS
21
SINGLE PT.
CONNECTION
FOR
ELECT.HEAT
HPS
CAP
23
C
11
13
TRAN
IFB
COMP
R
EQUIP.
GND
SEE HEATER
SCHEMATIC
FOR WIRING
S
BLU
BLU
FIELD SPLICE
TERMINAL (MARKED)
ENERGIZED
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
C1
C
C2
C CONTACTOR
CAP CAPACITOR
CCH CRANK CASE HEATER
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
NOTES:
IFM
HC F
C
& 3 (15 KW)
LPS
COLOR CODE
BLK BLACK
BLU BLUE
BRN BROWN
GRY GRAY
GRN GREEN
ORN ORANGE
PNK PINK
RED RED
VIO VIOLET
WHT WHITE
YEL YELLOW
CONTROL BOX AREA
BRN
BRN
LEGEND
OFM
INDOOR FAN
SECTION
& 4 (20 KW)
HR3
HR1,2
BLK
UNIT COMPONENT ARRANGEMENT
OUTDOOR FAN
SECTION
3
HR2
BRN
1
HR4
HR1 & 2 (10 KW)
GRY
1
BRN
3
BRN
VIO
HPS
BLK
COMPRESSOR
SECTION
BRN
HR1
1
GRY
VIO
W3
1
1
2
3
4
5
BLU
VIO
C
W2
W2
W3
W3
GRN
HR1 (5 KW)
WHT
1
1
2
3
4
5
6
7
G
DH
1
Y
Y1
R
C
Y1/Y
G
Y2/DH
W2
W3
12
PNK
PNK
YEL
BLU
GND
ECON
P1
BLU
YEL
6
RED
FU2 5 AMP
BLK
7
BLK
SEE NOTE
BLK
ECON
PLUG
7
FOR WIRING WITH
ELECTRIC HEATERS
SEE SCHEMATIC
ON HEATER
ACCESSORY.
RED
BLK
50VL-- A
FIELD
SUPPLY
POWER
SCHEMATIC
460-3-60
IF USED
CCH
DISCONNECT
PER NEC
CCH
24V SPLICE
BOX
24V POWER ENTRY
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.
A10204C
Fig. 14 -- Connection Wiring Diagram 460--3--60
21
LADDER WIRING DIAGRAM
DANGER: ELECTRICAL SHOCK HAZARD DISCONNECT POWER BEFORE SERVICING
L1
L2
L3
G/Y
BLK
11
BLK
IF USED
21
11
YEL
CCH
RED
C
23
BLK
13
GRN
OFM
R
C
S
BLK
YEL
BRN
YEL
CAP
BLU
T1
50VL-- A
BLK
T2
YEL
T3
COMP
BLK
11
YEL
C L G NX
13
G/Y
IFM
460V
TRAN
BLK
RED
SEE NOTE
7
Y1
G
DH
P1-1
P1-2
RED
BRN
YEL
W2
WHT
W3
VIO
Y2
VIO
13
G/Y
"R"
"C"
P1-3
P1-4
P1-5
GRN
BLU
YEL
24V
IFB
FUSE
3A
R
C
24V
24VAC
RED
460V
"Y1/Y"
"G"
"Y2/DH"
P1-6
P1-7
"W2"
"W3"
P2-1
P2-2
P2-3
P2-4
LPS
HPS
Y
BLK
BLK
BLU
C1
BLU
C
C2
BRN
C,TRAN
ACCESSORY
ELECTRIC HEAT
BRN
YEL
P4-1
WHT
WHT
HR1
P4-2
VIO
VIO
HR4
P4-3
PNK
PNK
HR2
P4-4
GRY
GRY
HR3
P4-5
BRN
BRN
LOW
SEE NOTE
STD
DEHUM
HIGH
C
G/Y
SEE NOTE
4
BRN
BLK
BRN
BRN
ECON
HARNESS
2
3
4
BRN
5
9
BLU
PNK
RED
ORN
BLK
1
2
3
4
IFM
C
BRN
COM C
6
PNK
BLU
7
PNK
BLU
SAT
8
5
BRN
RED
50VL500271
D
A10204
Fig. 14 Cont. -- Ladder Wiring Diagram 460--3--60
22
50VL-- A
A09089
Fig. 15 -- Cooling Charging Chart
23
MAINTENANCE
Air Filter
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.
!
PERSONAL
HAZARD
WARNING
INJURY
AND
UNIT
Indoor Blower and Motor
DAMAGE
Failure to follow this warning could result in personal
injury or death and possible unit component damage.
50VL-- A
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 Table 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.
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.
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
attempt to perform any maintenance on this equipment,
other than those procedures recommended in the Owner’s
Manual.
!
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.
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.
WARNING
ELECTRICAL SHOCK AND FIRE HAZARD
!
!
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
FAN GRILLE
MOTOR
A
MOTOR SHAFT
A08505
“A”
SIZE
IN.
6.3
6.3
7.3
7.6
7.6
7.6
24
30
36
42
48
60
MM
160
160
185
193
193
193
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
!
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.
Compressor
Access Panel
Blower
Access
Panel
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.
Control
Access
Panel
A09214
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
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
50VL-- A
MAX DISTANCE BETWEEN TOP OF FAN GRILLE AND BOTTOM OF FAN BLADE
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
50VL-- A
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
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.
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.
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.
!
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
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.
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.
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
WARNING
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
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
approximate 10 x 10 ft (3 x 3 m) area.
2. Cover area in front of the unit service panel with a terry
cloth shop towel to absorb lubricant spills, prevent run--offs,
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.
27
50VL-- A
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.
Table 10 – Troubleshooting Chart
SYMPTOM
Compressor and outdoor fan will not start
Compressor will not start but condenser fan
runs
CAUSE
Power failure
Fuse blown or circuit breaker tripped
Defective contactor, transformer, control relay, or high-pressure, loss--of--charge or low--pressure switch
Insufficient line voltage
Incorrect or faulty wiring
Thermostat setting too low/too high
Faulty wiring or circuit
Loose connections in compressor
Compressor motor burned out, seized, or
internal overload open
Defective run capacitor, overload, or PTC (positive
temperature coefficient) thermistor
One leg of 3--phase power dead
50VL-- A
Low input voltage
Three--phase scroll compressor (size 30-60 unit) has a low pressure differential
Scroll compressor is rotating in the wrong direction
Refrigerant overcharge or undercharge
Compressor cycles (other than normally
satisfying) cooling/heating calls
Compressor operates continuously
Defective compressor
Insufficient line voltage
Blocked outdoor coil
Defective run/start capacitor, overload or start relay
Faulty outdoor fan motor or capacitor
Restriction in refrigerant system
Dirty air filter
Unit undersized for load
Thermostat temperature set too low
Low refrigerant charge
Air in system
Excessive head pressure
Outdoor coil dirty or restricted
Dirty air filter
Dirty indoor or outdoor coil
Refrigerant overcharged
Air in system
Head pressure too low
Excessive suction pressure
Suction pressure too low
Indoor or outdoor air restricted or air short--cycling
Low refrigerant charge
Restriction in liquid tube
Refrigerant overcharged
Dirty air filter
Low refrigerant charge
Metering device or low side restricted
Insufficient coil airflow
Temperature too low in conditioned area
Outdoor ambient below 55°F (13°C)
Filter drier restricted
28
REMEDY
Call power company
Replace fuse or reset circuit breaker
Replace component
Determine cause and correct
Check wiring diagram and rewire correctly
Reset thermostat setting
Check wiring and repair or replace
Determine cause
Replace compressor
Determine cause and replace
Replace fuse or reset circuit breaker
Determine cause
Determine cause and correct
Correct the direction of rotation by reversing the
3--phase power leads to the unit
Recover refrigerant, evacuate system, and recharge to capacities shown on rating plate
Replace and determine cause
Determine cause and correct
Determine cause and correct
Determine cause and replace
Replace
Locate restriction and remove
Replace filter
Decrease load or increase unit size
Reset thermostat setting
Locate leak, repair, and recharge
Recover refrigerant, evacuate system, and recharge
Clean coil or remove restriction
Replace filter
Clean coil
Recover excess refrigerant
Recover refrigerant, evacuate system, and recharge
Determine cause and correct
Check for leaks, repair and recharge
Remove restriction
Recover excess refrigerant
Replace filter
Check for leaks, repair and recharge
Remove source of restriction
Check filter–replace if necessary
Reset thermostat setting
Install low--ambient kit
Replace
AIR CONDITIONER WITH PURON (R--410A) QUICK REFERENCE GUIDE
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.
29
50VL-- A
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.
START--UP CHECKLIST
(Remove and Store in Job Files)
50VL-- A
I. PRELIMINARY INFORMATION
MODEL NO.:
SERIAL NO.:
DATE:
TECHNICIAN:
II. PRESTART--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
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
* Measured 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 right to change, at any time, specifications and designs without notice and without obligations.
30
Catalog No:50VL---08SI
Replaces: 50VL--- 07SI
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