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REFRIGERANT TUBING — Connect tubing to fittings on out-
door unit vapor and liquid service valves. (See Fig. 2 and 5.)
SWEAT CONNECTION — Use refrigerant grade tubing. Service
valves are closed from factory and ready for brazing. After
wrapping service valve with a wet cloth, tubing set can be brazed
to service valve using either silver bearing or non-silver bearing
brazing material. Consult local code requirements. Refrigerant
tubing and indoor coil are now ready for leak testing. This check
should include all field and factory joints.
Step 6—Make Electrical Connections
To avoid personal injury or death, do not supply power to unit
with compressor terminal box cover removed.
Be sure field wiring complies with local and national fire, safety,
and electrical codes, and voltage to system is within limits shown
on unit rating plate. Contact local power company for correction of
improper voltage. See unit rating plate for recommended circuit
protection device.
NOTE:
Operation of unit on improper line voltage constitutes
abuse and could affect unit reliability. See unit rating plate. Do not
install unit in system where voltage may fluctuate above or below
permissible limits.
NOTE:
Use copper wire only between disconnect switch and
unit.
NOTE:
Install branch circuit disconnect per local codes to handle
unit starting current. Locate disconnect within sight from and
readily accessible from unit per local codes.
ROUTE GROUND AND POWER WIRES — Remove access
panel and control box cover to gain access to unit wiring. Extend
wires from disconnect through power wiring hole provided and
into unit control box. (See Fig. 2.) Size wires per local codes but
not smaller than minimum wire size shown on unit rating plate.
CONNECT GROUND AND POWER WIRES — Connect ground
wire to ground connection in control box for safety. Connect
power wiring to contactor as shown in Fig. 6.
The unit cabinet must have an uninterrupted or unbroken
ground to minimize personal injury if an electrical fault
should occur. The ground may consist of electrical wire or
metal conduit when installed in accordance with existing
electrical codes. Failure to follow this warning can result in an
electric shock, fire, or death.
NOTE:
Use No. 18 AWG (American Wire Gage) color-coded,
insulated (35°C minimum) wires. If thermostat is located more
than 100 ft (30.5m) from unit (as measured along the control
voltage wires), use No. 16 AWG color-coded wires to avoid
excessive voltage drop.
CONNECT CONTROL WIRING — Route 24-v control wires
through control wiring grommet and connect leads to control
wiring terminal board. (See Fig. 7.)
Use furnace transformer, fan coil transformer, or accessory trans-
former for control power, 24-v/40-va minimum.
NOTE:
Use of available 24-v accessories may exceed the mini-
mum 40-va power requirement. Determine total transformer load-
ing and increase the transformer capacity or split the load with an
accessory transformer as required.
NOTE:
The defrost timer is factory set for 90-minute cycles. The
timer can be field set for 30- and 50-minute cycles depending on
defrost conditions in your geographic location.
Step 7—Compressor Crankcase Heater
When equipped with a crankcase heater, energize heater a mini-
mum of 24 hr before starting unit. To energize heater only, set
thermostat to OFF and close electrical disconnect to outdoor unit.
A crankcase heater is required if the refrigerant tubing is longer
than 50 ft.
Step 8—Install Electrical Accessories
Refer to the individual instructions packaged with the kits or
accessories when installing.
Step 9—Start-up and Check Charge
To prevent compressor damage or personal injury, observe
the following:
• Do not overcharge system with refrigerant.
• Do not operate unit in a vacuum or at negative pressure.
• Do not disable low-pressure switch
In scroll compressor applications:
• Dome temperatures may be hot.
To prevent personal injury wear safety glasses, protective
clothing, and gloves when handling refrigerant and observe
the following:
• Back seating service valves are not equipped with Schrader
valves. Fully back seat (counter clockwise) valve stem before
removing gage port cap.
• Front seating service valves are equipped with Schrader
valves.
Fig. 6—Line Power Connections
A96650
FIELD POWER
WIRING
DISCONNECT PER
IEC AND/OR
LOCAL CODES
N FOR 1-PHASE ONLY
3-PHASE ONLY
CONTACTOR
L1
L2/N
L3
PE
L1
L2/N
L3
PE
GROUND
LUG
4