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For buried-line applications greater than 36 in., consult your local
distributor.
If refrigerant tubes or indoor coil are exposed to atmosphere, they
must be evacuated to 500 microns to eliminate contamination and
moisture in the system.
OUTDOOR UNIT CONNECTED TO FACTORY-APPROVED
INDOOR UNIT
Outdoor unit contains correct system refrigerant charge for opera-
tion with indoor unit of same size when connected by 15 ft of
field-supplied or factory-accessory tubing. Check refrigerant
charge for maximum efficiency.
REFRIGERANT TUBING
Connect tubing to fittings on outdoor unit vapor and liquid service
valves. (See Table 1.) Use refrigerant grade tubing.
SWEAT CONNECTION
To avoid valve damage while brazing, service valves must be
wrapped in a heat-sinking material such as a wet cloth.
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.
IMPORTANT:
Check to be certain factory tubing on both indoor
and outdoor unit has not shifted during shipment. Ensure tubes are
not rubbing against each other or any sheet metal. Pay close
attention to feeder tubes, making sure wire ties on feeder tubes are
secure and tight.
Step 9—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 of adequate size per
NEC to handle unit starting current. Locate disconnect within sight
from and readily accessible from unit, per Section 440-14 of NEC.
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.
Table 1—Refrigerant Connections and Recommended Liquid and Vapor Tube Diameters (In.)
UNIT
SIZE
LIQUID
VAPOR
VAPOR (LONG LINE)
Connection Diameter
Tube Diameter
Connection Diameter
Tube Diameter
Connection Diameter
Tube Diameter
024
3/8
3/8
5/8
5/8
5/8
3/4
030, 036
3/8
3/8
3/4
3/4
3/4
7/8
042, 048
3/8
3/8
7/8
7/8
7/8
7/8
NOTES:
1. Tube diameters are for lengths up to 50 ft. For tubing lengths greater than 50 ft, consult Residential Split System Long-Line Application Guideline.
2. Do not apply capillary tube indoor coils to these units.
Table 2—Accessory Usage
ACCESSORY
REQUIRED FOR
LOW-AMBIENT
APPLICATIONS
(BELOW 55°F)
REQUIRED FOR
LONG-LINE
APPLICATIONS*
(OVER 50 FT)
Crankcase Heater
Yes
Yes
Evaporator Freeze Thermostat
Yes
No
Accumulator
No
No
Compressor Start Assist
Capacitor and Relay
Yes
Yes
MotorMaster® Control,
or
Low-Ambient Pressure Switch
Yes
No
Wind Baffle
See Low-Ambient Instructions
No
Support Feet
Recommended
No
Liquid-Line Solenoid Valve
or
Hard Shutoff TXV
No
See Long-Line
Application
Guideline
Ball Bearing Fan Motor
Yes‡
No
* For tubing line sets between 50 and 175 ft, refer to Residential Split System Long-Line Application Guideline.
‡ Required for Low-Ambient Controller (full modulation feature) and MotorMaster Control only.
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