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3
Table 1 – Accessory Usage
Accessory
REQUIRED FOR LOW–AMBIENT
COOLING APPLICATIONS
(Below 55
F / 12.8
C)
REQUIRED FOR
LONG LINE APPLICATIONS*
REQUIRED FOR
SEA COAST APPLICATIONS
(Within 2 miles / 3.22 km)
Accumulator
Standard
Standard
Standard
Ball Bearing Fan Motor
Yes
{
No
No
Compressor Start Assist Capacitor and
Relay
Yes
Yes
No
Crankcase Heater
Yes
Yes
No
Evaporator Freeze Thermostat
Yes
No
No
Hard Shutoff TXV
Yes
Yes
Yes
Isolation Relay
Yes
No
No
Liquid Line Solenoid Valve
No
See Long–Line Application Guideline
No
Motor Master
Control or
Low Ambient Switch
Yes
No
No
Support Feet
Recommended
No
Recommended
* For tubing line sets between 80 and 200 ft. (24.38 and 60.96 m) and/or 20 ft. (6.09 m) vertical differential, refer to Residential Piping and Longline Guideline. .
{
Additional requirement for Low–Ambient Controller (full modulation feature) MotorMaster
r
Control.
Make Piping Connections
!
WARNING
PERSONAL INJURY AND ENVIRONMENTAL
HAZARD
Failure to follow this warning could result in personal injury
or death.
Relieve pressure and recover all refrigerant before system
repair or final unit disposal.
Use all service ports and open all flow–control devices,
including solenoid valves.
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
If ANY refrigerant tubing is buried, provide a 6–in (152.4
mm). vertical rise at service valve. Refrigerant tubing lengths
up to 36–in (914.4 mm). may be buried without further special
consideration. Do not bury lines longer than 36 in (914.4 mm).
Outdoor units may be connected to indoor section using accessory
tubing package or field–supplied refrigerant grade tubing of correct
size and condition. For tubing requirements beyond 80 ft,
substantial capacity and performance losses can occur. Following
the recommendations in the
Residential Piping and Long Line
Guideline
will reduce these losses. Refer to Table 1 for accessory
requirements. Refer to Table 2 for field tubing diameters.
There are no buried–line applications greater than 36 in. (914.4
mm)
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 approximate system refrigerant charge for
operation with approved AHRI rated indoor unit when connected
by 15 ft (4.57 m) of field–supplied or factory–accessory tubing,
and factory supplied filter drier.
Some indoor units require
additional subcooling to achieve optimal heating performance.
Using Table 5 or 6– Additional Subcooling Required, check
refrigerant charge for maximum efficiency
Refrigerant Tubing and Sweat Connections
Connect vapor tube to fitting on outdoor unit vapor service valves
(see Table 2). Connect liquid tubing to adapter tube on liquid
service valve. Use refrigerant grade tubing.
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
Service valves must be wrapped in a heat–sinking material
such as a wet cloth while brazing.
Remove plastic retainer holding outdoor piston in liquid service
valve, leaving the piston and piston retainer inside the valve.
Connect sweat/flare adapter provided, to valve. (See Fig. 4.)
Connect refrigerant tubing to fittings on outdoor unit vapor and
liquid service valves. 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. Do not use soft solder
(materials which melt below 800
°
F/427
°
C). Consult local code
requirements. Refrigerant tubing and indoor coil are now ready for
leak testing. This check should include all field and factory joints.
NOTE
: Some outdoor units contain a mechanical fitting at the
liquid distributor. This connection is not field serviceable and
should not be disturbed.
A05226
Fig. 4 -- Liquid Service Valve
25H
B
B
/25H
B
C
/25H
C
D
Always Ask For