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How To Tell if My AUX Compressor is Working?

May 24, 2015, 12:24:28 pm

Good Morning All!

I ocassionally hear my HWH let some air out of an air bag.

But I cannot recall ever hearing the aux compressor do anything.

We did find and fix a broken wire on the aux compressor when we got back from Bernd's shop last August.

best, paul

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Re: How To Tell if My AUX Compressor is Working?

Reply #1 – May 24, 2015, 12:34:10 pm

If you don to have slides it will keep the main tank at somewhere between 30 and 60 lbs of air.  At least my 99 did that with no slides. If you do not have slides it is not a big issue as the bladders are not present.  I will say I rarely heard it run on the non slide coaches it runs more on my bigger coach with slides and when I open and shut the slides it is always running to drain the bladder and to refill them.

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Re: How To Tell if My AUX Compressor is Working?

Reply #2 – May 24, 2015, 04:51:37 pm

Paul,

On my non-slide coach, I normally store it with the leveling system off.  Over time, the tanks bleed down and the air bags bleed down.  Because of my parking area, it ends up nose low and listing to port.  If, after several weeks, I turn the ignition on (but not start the engine) and request the HWH system to level the coach, it will begin leveling with whatever air is still left in the system.  But very soon the aux compressor comes on to complete the job.  That is the only situation I have ever heard that pump come on. 

Richard

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Re: How To Tell if My AUX Compressor is Working?

Reply #3 – May 24, 2015, 06:29:01 pm

Most common situation: We sometimes park in a space where the coach cannot achieve level, especially "front to back".  If we leave the HWH system ON in that position, it will "wake up" every 30 minutes, see that the coach is not level, and attempt to correct.  Since the air bags are already "empty" at one end and fully extended at the other, the pump will run for about 10-15 minutes trying to correct the situation.  Then it gives up, HWH panel turns on all 4 yellow lights, and goes back to sleep.  Repeats every 30 minutes until I turn off the HWH panel power.

Another situation: If you empty your air tanks, then try to use the manual "Raise" function on the HWH panel, the AUX compressor should run.

There is (usually) a in-line fuse on the power lead at the compressor.  Later models may also have a ON/OFF switch at the pump.

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Re: How To Tell if My AUX Compressor is Working?

Reply #4 – June 04, 2015, 07:40:18 pm

Well, I notice my 2 tanks maintain a pressure of 32psi.

So it seems my Aux Compressor is working.

But I haven't heard it yet.

best, paul

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Re: How To Tell if My AUX Compressor is Working?

Reply #5 – June 04, 2015, 08:26:18 pm

Not correct. The aux pump does NOT add air to tanks. There are different ways you can level your coach, however the HWH system has a priority. If you are out of level and your tanks contain +85 lbs, the system will EXHAUST the high side until level and will keep doing this until -85psi. Once your tank level is less than 85 there is a pressure switch on the aux pump set at 85'ish. Rather than exhaust it will now activate and INCREASE the psi in the bags only until level.

In order to see if your aux compressor works, you simply hit the on button once and then hold any up arrow so it is activated. You will hear the compressor come on no matter what psi in the tanks. Does it raise the coach? Hold it down until an "out of level" light comes on. Sometimes it may take 15 minutes but no more. If the "out of level" light comes on, it raised the bags enough to create the out of level condition.

A normal "at rest" psi in the tanks would be around 50-60 psi but mine sometimes go to 0 which is no big deal to me.

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Re: How To Tell if My AUX Compressor is Working?

Reply #6 – June 04, 2015, 08:56:32 pm

Paul, some coaches had a button near or on the HWH panel whereby you could add aux compressor air to the two main, brake, tanks.  I do not know when this was common, but a Tech thought I had such as switch on a 2001 but I do not on mine.

Also the aux compressor will try to add air to the main tanks if there is an error in a particular check valve.  If you hear it running to do that, I advise.....based on my coach.....that you do not allow it to try to air the main tanks up from my trigger point of 70 psi to 120 psi.  I have been told that may burn out the aux compressor.  I added a switch that I no longer have to pull the compressor fuse to stop it.  I seldom if ever have mine run more than 4 minutes to replenish the air in the third tank that is used for the leveling when aux compressor air is needed.  However mine no longer tries to air up the main two tanks on its own, I got that solved.    I do have a slide system, but slide or not, you have the aux compressor on yours.  You can trigger its operation as was covered above, then feel it.....it will get quite warm.

On my coach, the two main air tanks do not drop below 70 psi for at least several weeks and perhaps even longer.  I know they held for over a month in the past.

I think I have this right, hope for corrections if in error so as to not mislead you.

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Reply #7 – June 05, 2015, 11:06:48 am

Thanks! Worked like a charm.

But all I heard was a click.

No noise like something running,  Out of level light came on so it must be doing its job.

best, paul

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Re: How To Tell if My AUX Compressor is Working?

Reply #8 – June 05, 2015, 11:11:58 am

Paul, I can just barely hear ours while in the coach.  No TV on, etc.  But if I think that I hear it, I go outside and feel the compressor, you will know it running, it vibrates and will get warm, until shuts off.  Even for a while you can feel it is warm, evidence it ran.  Mine usually shuts off right at four minutes of running, not longer unless a problem, such as a leak or trying to air the main tanks, which it should not do.....on mine.

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Re: How To Tell if My AUX Compressor is Working?

Reply #9 – June 05, 2015, 04:13:47 pm

You are correct. If the light went on, it works. Lucky you to have silence.

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