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Home » Public Forums » GMCnet » Re: [GMCnet] I keep blowing compressor outlet hose (and check your accumulator)
Re: [GMCnet] I keep blowing compressor outlet hose (and check your accumulator) [message #83252] Wed, 05 May 2010 18:45
glennbrien is currently offline  glennbrien   United States
Messages: 4
Registered: June 2009
Karma: 0
Junior Member


First of all, thanks to everyone who offered advice on the compressor. I knew I'd get some flak for the non-original hose, but it was a calculated risk- located in a closet if it blew again, and the bags wouldn't lose pressure because of it due to its particular placement in the system. I had the material lying around, and it was a way to keep the system functional while I sorted things out. I haven't actually done any traveling in this coach yet. Here are some observations, now that I've tested it:
1.) I have the original type compressor- a two-cylinder unit with a big "GMC" logo on it.
2.) I put a brass tee in, with a 0-160 pressure gauge, so I could monito the pressure as it came up.
3.) I used more ice machine hose, simply so I could see if it blew below 120 psi. I'll replace it with approved stuff before I actually trust it.
4.) My pressure switch IS stuck- I ran over and turned it off as soon as it started creeping above 120 psi, it was showing 125 when I shut it down. The pressure switch did not respond to adjustment, even when turned all the way down. I checked it with an ohm meter, it's closed with the adjuster fully loose. (Side note: the icemaker hose held at that pressure, I suppose it could be used in a pinch. It's from an icemaker installation kit from Home Depot.)
5.) I decided to pull the schrader valve from the bottom of the acumulator, to let out any water that might be trapped in it. I was surprised that no water came out, but the schrader valve core felt damp. I poked an appropriately-sized allen wrench up into the valve hole to see if it was obstructed, and guess what? water dumped out, looked like a few ounces at least but I didn't have the foresight to catch and measure it.
I thought I'd share that last bit since I haven't seen any posts on this issue. To me, it implies that if you simply press in the tip of the valve to check for water in the system you may think it's dry when it's really clogged and holding water.
Thanks again for the advice. My system is diagnosed, I need a pressure switch!
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