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Topic: Coach a.c.  (Read 906 times) previous topic - next topic

Coach a.c.

Installed new compressor and dryer on my '97 U320 yesterday. 5.5 lbs of R134a as recommended by Mark of FT tech support. It IS cooling, but the discharge air temp is about 68 degrees, not cool enough to be of real benefit.

Is there an expansion valve or orifice somewhere that needs replacing? Any suggestions would be greatly appreciated.

Duane Budd
dcbudd@embarqmail.com
Johnson City, TN
'97 U320TB / Cobalt Toad

Re: Coach a.c.

Reply #1 –
Dwayne, Our caches may not be exactly the same ......
On mine, The charge of 134a is not relevant, there is 36 feet of hose to the compressor.  MY method is.. Start AC, jump across freeze stat ( low temp control ) to ensure that compressor is running,  Then remove jumper. watch sight glass at dryer, when bubbles STOP you should have right charge of 134a.  If you miss the mark, release 134a til you get just a slight amount. I have 42 Degrees at the evaporator.  I have two known leaks and I have to repeat this procedure about once a year.  It works best when outside temp is high, 85 or better.  A competent AC shop should be able to do the same using the readings on an ACCURATE set of gauges as there is a direct correlation between TEMP, and PREESSURE.
Good luck
 

Re: Coach a.c.

Reply #2 –
I have a 96 U320 and had to recharge the dash AC after I bought it in March. There was some pressure so system was not empty. I added 9 12oz cans of 134a which is 108oz, while 5.5lbs is only 88oz, does not sound like enough to me for an empty system. I kept adding until dash air blew cold  (testing with an infrared temperature sensor).
Wyatt in Victoria
1996 U320 40 WTFE
1998 Suzuki X90 Towd
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada