Piper Arrow IV Turbo Maintenance Manual page 135

(7) When Loctite Refrigerant Sealant has been used on a joint it must be heated to 400°F prior to
disassembly. Loctite must be used to seal any pipe threads in the system lines.
(8) Replace the receiver-dehydrator assembly on any system which has been operating with a leak
allowing air to enter the system. If a receiver-dehydrator is left open to the atmosphere it should be
replaced due to the loss of effectiveness of the drying compound it contains.
A very strong acid (HCL) is formed when R-12 comes in contact
with moisture.
A new receiver-dehydrator should be opened and connected to
the system only when ready to charge the system with refrigerant.
(9) Recommended torque values must be used on all flare fitting and O-ring joints. (See Chart 2104.)
Metal Tube
O. D.
1/4
3/8
1/2
5/8
3/4
SERVICE VALVES.
The purpose of the service valve is to service the air conditioning system. (Testing, Bleeding, Evacuating
and Charging) This aircraft is equipped with service valves mounted in the suction and discharge lines of the
evaporator assembly. These valves are the "2" position type Schrader valves. All normal air conditioning
service should be performed at the evaporator assembly mounted valves.
Service valves are also located on the compressor. However, use
of these valves in servicing is not recommended.
If a Schrader service valve is not serviceable, the core assembly
must be replaced.
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL
—NOTE—
CHART 2104. ALUMINUM TUBING TORQUE
Thread and Fitting
Size
7/16
5/8
3/4
7/8
1-1/16
—NOTE—
—NOTE—
1F15
Alum. Tubing
Torque
5-7 ft.-lbs.
11-13 ft.-lbs.
15-20 ft.-lbs.
21-27 ft.-lbs.
28-33 ft.-lbs.
21-50-04
Page 21-16
December 1, 1978