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Topic: Another Air compressor issue. (Read 855 times) previous topic - next topic

Another Air compressor issue.

My compressor is doing something I'm not sure about.  I have included a video that shows the problem.  First, I'm loosing air pressure at a very low rate.  When camping and the coach in the level position the compressor will kick on 2 or three times a day for 1-2 minutes.  This does not seem to be bad in itself.  But the problem is that sometimes, not every time, when the compressor kicks on it blow off valve will continue to blow off and the compressor will not shut off until I pull the fuse.  My guess is that the blowoff valve is blowing off before the air pressure reaches the cut off air pressure level, and not allowing the compressor to shut off.   

The last time we were out was over the holidays.  One night I woke up to the sound of the compressor and the blow off value.  The compression sound itself is not enough to wake me up, but the blowoff valve kicks the noise up a good notch or two.  The compressor ran for a good 15 minute before it registered in my very sleepy head that there was a problem.  When the engine is running the pressure seems normal and I don't perceive a problem.
 
In the video I've attached below, I had the engine running and the dash gauges were both reading over 125psi.  I also have the coach system digital display show over 125psi.  Next I shut off the engine and I heard the Aux compressor running and the blow off valve blowing off. 

So I'm hoping that someone can give me some advice as to what I can do. 

One other thing about my air pressure.  I did a little experiment the other day.  I raised the coach to it's highest level, I pulled the fuse for the aux compressor.  The coach was in storage and I closed it up and went away for 3 days.  When I came back my gages were both reading 0psi.  All the air bags were still filled as were the slide seals.  So I'm guessing the air is leaking in the break system.  I can not hear any air leaking as I did 6 months ago when I was able to find a leak and make the repair.

So any ideas?

http://youtu.be/kZccCc5qY38
David
2004 U320
This is my good stuff

Re: Another Air compressor issue.

Reply #1 –
Dave,

  In the video I noticed that the desiccant was almost all pink in color! Could it be that the flow of air is being restricted by all that moisture? That happened to me- because I forgot all about checking the state of my desiccant. Just an observation.

Ed Pan


Ed Pan, M.D.
2002 U320 40'

Re: Another Air compressor issue.

Reply #2 –
Suggest checking or replacing the pressure switch on the electric compressor, not costly and should be straight forward, IE simple.
Doubtful but possible that someone turned the switch at too high pressure ?
Dave M

Re: Another Air compressor issue.

Reply #3 –
Dave,
I notice on you video the the ring on the high pressure relief moved when the compressor was running. Are you getting air coming out of the pressure relief valve. Sometimes the pressure relief valve dose not seat as it should thus causing a leak. Karl

Re: Another Air compressor issue.

Reply #4 –
A spray bottle with soapy water mixture. Spray on suspected areas and look for bubbles.
Good luck,
Rick

Re: Another Air compressor issue.

Reply #5 –
Rick's advice is spot-on.  Steve's found and fixed leaks at a number of the connections in that area, including the check valve itself and the quick connect fittings (we replace them with DOT ones).

Your description of the blowoff valve and compressor running are extremely familiar.  That valve has been a problem for us in the past - debris, etc. on the seat have caused it to continue to leak air and the compressor to run.  Steve rebuilt one of ours and we carry it as a spare.  HWH Solenoid Valve Rebuild (note that Steve wrote that first post, not me ;)  )

HTH,

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Another Air compressor issue.

Reply #6 –
Quote from: Ed Pan –
Dave,

  In the video I noticed that the desiccant was almost all pink in color! Could it be that the flow of air is being restricted by all that moisture? That happened to me- because I forgot all about checking the state of my desiccant. Just an observation.

Ed Pan

Ed, I see what your talking about.  I'm still quite green and I have not heard about checking the desiccant.  Is this a part/substance that you need to get form Foretravel?  I'll have a look at it when I get over there this afternoon. 
David
2004 U320
This is my good stuff

Re: Another Air compressor issue.

Reply #7 –
Quote from: Dave M –
Suggest checking or replacing the pressure switch on the electric compressor, not costly and should be straight forward, IE simple.
Doubtful but possible that someone turned the switch at too high pressure ?
Dave M

Thanks Dave, this sounds like something I want to check.  Is this switch attached to the the compressor?
David
2004 U320
This is my good stuff

Re: Another Air compressor issue.

Reply #8 –
Quote from: David and Rita –

Ed, I see what your talking about.  I'm still quite green and I have not heard about checking the desiccant.  Is this a part/substance that you need to get form Foretravel?

Or Grainger, if you want to pay close to $50/4 ounce bag, yes...

Or you can regenerate the existing and/or bag your own:


Regenerating HWH desiccant

Desiccant option for the HWH system

DIY Desiccant (was What did you do to your coach today)

BTW last time I ordered from Sorbent there was a "handling fee" for small orders.  I didn't see the smaller quantity of non-cobalt desiccant (the environmentally-friendlier orange to green-changing one) on their website - would be worth a call/e-mail if you want to look into that "flavor".

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Another Air compressor issue.

Reply #9 –
Thank you Dave M,  I was able to make a small adjustment to the compressor pressure switch.  I put the fuze in it's holder and let the air build up to the point when it was blowing off and I let the nut that holds the spring on the switch out one half turn.  It immediately stopped blowing off.  I then went in and bleed off some air by pumping the brakes, and lifted the coach up and down.  At about 50psi the compressor started and within about 12 minutes (total guess) the pressure was up to 105psi and the compressor stopped, and the HWH went back to sleep. 

I also regenerated my desiccant and now it's nice and blue.  So thanks to all the advice, other than loosing a small amount of air pressure, at what may be an except able rate, I think I'm good.  This forum once again is a wealth of knowledge. I hate to think what it would have cost me to have taken the coach in to a shop/dealer and said "can you fix my air problem". I'm in Arizona and not retired, so trips to Nac will be few and far between for sometime to come.

Thanks again
David
2004 U320
This is my good stuff
 

Re: Another Air compressor issue.

Reply #10 –
David,
Glad to offer the suggestion, from your description, that was the most likey direction I could guess.  Glad it was the simple easy route.
Happy for all
Dave M