Leak Detection - Piper CHEROKEE WARRIOR PA-28-151 1995 Maintenance Manual

PIPER CHEROKEE WARRIOR SERVICE MANUAL
1 3 . When High side manifold hand set gauge indicates a little below zero, open High s i d e
m a n ifold hand set valve and continue evacuation.
14. Operate vacuum pump for 0:15 minutes, or until manifold hand set low side gauge indicates
24 to 26 inches of mercury (in. Hg.), whichever occurs first.
15. Close manifold hand set low side and high side valves.
16. Stop vacuum pump and observe manifold hand set low side gauge. If gauge rises at a rate
greater than 1 in. Hg. in 0:05 minutes, there is a leak in the system. Locate leak as described in paragraph 4,

Leak Detection.

17. Repair leak. Repeat steps (7) through (15) as necessary.
18. With the manifold hand set low side and high side valves OPEN, continue pumping, holding
system below 26 in. Hg. for a minimum of 30 minutes.
All specified pumping times may be included in the 0:30
m i nutes, provided no blockage or leaks ore noted, and provided
the system is not opened by disconnecting or removing
c o m p onents.
19. When panel display reads CPL (complete), close the manifold hand set low side and high side
valves. Perform charging procedure immediately. (Refer to paragraph 14-14.)
14-11. LEAK DETECTION.
a. Using the Robinair 34700 charging/test station
If step a, 15, in paragraph 14.10 above, indicates a leak, and location of the leak is not obvious,
use the following procedure to locate leak.
1 . If recharge/test stand is not already connected to system, follow steps a, 1 through 4, in
p a r agraph 14.10 above.
2. Open the high side (2) valve and allow 1/2 pound of refrigerant to enter the system. Close
high (2) side valve. (Refer to Figures 14-6 and 14-7.)
3. Locate leak(s) using an electronic leak detector designed to detect R12. Or, use soap and
water in a thick solution.
4. Repair leak(s).
5. Discharge system per paragraph 14-12.
6. Perform evacuation procedure per paragraph 14-10, a.
7. Immediately perform charging procedure per paragraph 14-13.
b. Using A Manifold Hand Set.
If step b, 16, in paragraph 14.10 above, indicates a leak, and location of the leak is not obvious,
use the following procedure to locate leak.
1. Close both the low side and high side valves on manifold hand set.
2. Disconnect manifold hand set middle port (yellow ) hose from low side port on charging stand
and connect it to a container of R12.
3. Open refrigerant container service valve.
4. Open the manifold hand set high side valve until a pressure of 50 psig is reached on low side
gauge. Close high side valve.
Added: February 28, 1995
NOTE
WARNING
Do not use an open flame leak detector.
3B4
Island Enterprises
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