8. Ensure that tubing insulation is pliable and completely sur-
rounds the vapor line.
9. When necessary, use hangar straps which are 1 in. wide and
conform to the shape of the tubing insulation. (See Fig. 3.)
10. Isolate the hangar straps from the insulation by using metal
sleeves bent to conform to the shape of the insulation.
If refrigerant tubes or indoor coil is exposed to atmospheric
conditions for longer than 5 minutes, it 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 refrig-
erant charge for operation with indoor unit of the same size when
connected by 15 ft of field-supplied or factory accessory tubing.
Check refrigerant charge for maximum efficiency. (See Step
9—Checking Charge.) .
Table 1—Refrigerant Connections and Recom-
mended Liquid and Vapor Tube Diameters (In.)
UNIT
SIZE
LIQUID
VAPOR
Connect
Diameter
Tube
Diameter
Connect
Diameter
Tube
Diameter
018
3/8
3/8
5/8
5/8
024
3/8
3/8
5/8
3/4
030, 036
3/8
3/8
3/4
3/4
042
3/8
3/8
7/8
7/8
048
3/8
3/8
7/8
1-1/8
Note: Tube diameters are for lengths up to 50 ft. For tubing lengths greater
than 50 ft, consult Long-Line Application Guideline.
REFRIGERANT TUBING — Connect tubing to fittings on out-
door unit vapor and liquid service valves. (See Fig. 2 and 7.)
A brazing shield MUST be used when tubing sets are being
brazed to the service valves to prevent damage to the painted
unit surface.
To avoid valve damage while brazing, service valves must be
wrapped with a heat-sinking material such as a wet cloth.
SWEAT CONNECTION — Use refrigerant grade tubing. Service
valves are closed from factory 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. Remove plastic retainer covering threads
of liquid service valve and connect flare adapter provided to valve.
(See Fig. 7.) Consult local code requirements. Refrigerant tubing
and indoor coil are now ready for leak testing. This check should
include all field and factory joints.
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.
Fig. 3—Piping Installation
A92469
OUTDOOR WALL
CAULK
INDOOR WALL
LIQUID LINE
VAPOR LINE
INSULATION
JOIST
INSULATION
HANGER STRAP
(AROUND VAPOR
LINE ONLY)
VAPOR LINE
LIQUID
LINE
THROUGH THE WALL
SUSPENSION
1
″
MIN
NOTE:
AVOID CONTACT BETWEEN TUBING AND STRUCTURE
Fig. 4 —Accessory Heat Pump Feet
A88277
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