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Step 3—Clearance Requirements
When installing, allow sufficient space for airflow, wiring, refrig-
erant piping, and service. Allow 30 in. clearance to service end of
unit and 48 in. abouve unit. For proper airflow, a 6 in. clearance on
1 side of unit and 12 in. on all remaining sides must be maintained.
Maintain a distance of 24 in. between units. Position so water,
snow, or ice from roof or eaves cannot fall directly on unit.
On rooftop applications, locate unit at least 6 in. above roof
surface.
Step 4—Operating Ambients
The minimum outdoor operating ambient in cooling mode is 55°F,
and the maximum outdoor operating ambient in cooling mode is
125°F.
Step 5—Replace Indoor AccuRater® Piston, if Required
Check indoor coil piston to see if it matches the required piston
shown on unit rating plate. If it does not match, replace indoor coil
piston with piston shipped with this unit. The piston shipped with
outdoor unit is correct for any approved indoor coil combination.
Remove indoor coil piston if unit is to be installed on system
with a thermostatic expansion valve (TXV) metering device.
Step 6—Make Tubing Connections
Relieve pressure and recover all refrigerant before system
repair or final unit disposal to avoid personal injury or death.
Use all service ports and open all flow-control devices,
including solenoid valves.
If ANY refrigerant tubing is buried, provide a 6 in. vertical
rise at service valve. Refrigerant tubing lengths up to 36 in.
may be buried without further special consideration. For
lengths above 36 in., consult your local distributor.
To prevent damage to unit or service valves observe the
following:
• Use a brazing shield.
• Wrap service valves with wet cloth or use a heat sink
material.
Outdoor units may be connected to indoor section using accessory
tubing package or field-supplied refrigerant tubing of correct size
and condition. For tubing requirements beyond 50 ft, substantial
capacity and performance losses can occur. Following the recom-
mendations in the Residential Split System Long-Line Application
Guideline will reduce these losses. Refer to Table 1 for field tubing
equivalent line length. Refer to Table 2 for accessory require-
ments.
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 refriger-
ant charge for operation 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 out-
door unit vapor and liquid service valves. (See Table 1.) Use
refrigerant grade tubing.
SWEAT CONNECTION — Service valves are closed from fac-
tory and ready for brazing. After wrapping the service valve with
a wet cloth, the tubing set can be brazed to the service valve using
either silver bearing or non-silver bearing brazing material. Con-
sult local code requirements. Refrigerant tubing and indoor coil are
now ready for leak testing. This check should include all field and
factory joints.
To avoid valve damage while brazing, service valves must be
wrapped in a heat-sinking material such as a wet cloth.
Step 7—Make Electrical Connections
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 or phase imbalance may
fluctuate above or below permissible limits.
NOTE:
Use copper wire only between disconnect switch and
unit.
Fig. 3—Piping Installation
A94028
INSULATION
VAPOR TUBE
LIQUID TUBE
OUTDOOR WALL
INDOOR WALL
LIQUID TUBE
VAPOR TUBE
INSULATION
CAULK
Avoid contact between tubing and structure
NOTE:
THROUGH THE WALL
HANGER STRAP
(AROUND VAPOR
TUBE ONLY)
JOIST
1
″
MIN.
SUSPENSION
3
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