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Topic: Auxiliary Air Compressor Inoperative (Read 1223 times) previous topic - next topic

Auxiliary Air Compressor Inoperative

Air compressor had been running more frequently than I thought it should.  It was on my list to check it our before next trip.  Now it doesn't work at all.  I need to get the compressor running then begin looking for a leak. Where do I start troubleshooting?
Don & Sue
2009 NImbus 38
2020 Jeep Grand Cherokee toad

Re: Auxiliary Air Compressor Inoperative

Reply #1 –
Check fuse and power to pump

If power good tap pump with hammer lightly If that doesn't get it going remove from coach and take a look at pump
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: Auxiliary Air Compressor Inoperative

Reply #2 –
You likely have an on/off switch on the side panel next to the driver, make sure it is not off.  My pressure control switch gets stuck once in a while.  You have to remove the cover and manually open the contacts. 
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Auxiliary Air Compressor Inoperative

Reply #3 –
Air pressure is low.  I noticed that the pump does not come on when I attempted to extend the slides and the amber light did not stop blinking.  While the amber light was blinking I inspected the utility compartment and noticed an extra blinking red LED light that goes off when I turn the key off for the slide operation.  I haven't found the location of a fuse yet.  I did find the location of a HWH breaker but have not yet tested.
Don & Sue
2009 NImbus 38
2020 Jeep Grand Cherokee toad

Re: Auxiliary Air Compressor Inoperative

Reply #4 –
The bigger HWH breaker may be for the hydraulic pump.  there are in-line fuses near the compressor.  Your coach is different from mine so there is going to be some not so precise ideas.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Auxiliary Air Compressor Inoperative

Reply #5 –
Agree with Roger, HWH hyd pump is on 150 amp breaker and 12 air compressor is on smaller 40 amp one. Both on electrical panel behind compressor and hyd pump, at least on my coach, yours is probably different. On my coach, 12 volt compressor is only controlled by the pressure switch to maintain pressure. HWH uses the air for slide seals and leveling, but does not turn the compressor on or off.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Auxiliary Air Compressor Inoperative

Reply #6 –
Quote from: djpauls –
I noticed that the pump does not come on when I attempted to extend the slides and the amber light did not stop blinking.  While the amber light was blinking I inspected the utility compartment and noticed an extra blinking red LED light that goes off when I turn the key off for the slide operation.  I haven't found the location of a fuse yet. 

It's been years since we helped on a 2009 Nimbus, and I can't recall if it's exactly like our 2003 but I seem to remember it was close enough.  The fuse in question is an inline blade style feeding the Aux Compressor power and is in one of the wires going to the compressor itself.
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: Auxiliary Air Compressor Inoperative

Reply #7 –
This is a pic of the 40 amp breaker that feeds the 12 volt compressor. This power goes to a relay activated by the air pressure switch. The control voltage for the relay comes from pressure switch through a 15 amp fuse. The main breaker has a pop out reset on one side that would have to be pushed back in to reset. The 15 amp fuse is easy to check.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Auxiliary Air Compressor Inoperative

Reply #8 –
Finally had time to check it today.  40 amp breaker was tripped.  Reset and compressor ran, built up pressure and turned off.  Extended slide rooms and compressor came on and then would not shut off.  Continued to build pressure until air safety valve? began popping.  Only way to get it to stop was to pull the in-line 15 amp fuse (miserable thing to get to).  Additional tips?

Thanks to all for your help!
Don & Sue
2009 NImbus 38
2020 Jeep Grand Cherokee toad

Re: Auxiliary Air Compressor Inoperative

Reply #9 –
Quote from: djpauls –
Finally had time to check it today.  40 amp breaker was tripped.  Reset and compressor ran, built up pressure and turned off.  Extended slide rooms and compressor came on and then would not shut off.  Continued to build pressure until air safety valve? began popping.  Only way to get it to stop was to pull the in-line 15 amp fuse (miserable thing to get to).  Additional tips?

Thanks to all for your help!
Sounds like your pressure switch is stuck [gray box attached to discharge line from compressor]. Line from fuse should run to it. Has an contact held closed by a spring. When pressure reaches proper psi, spring is overcome and contacts open. Check contacts are not stuck closed.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Auxiliary Air Compressor Inoperative

Reply #10 –
White plastic plate is one side of contact, should not  touch bottom plate when pressure proper. Plate goes down an touches bottom plate when pressure falls.This completes circuit to relay and compressor starts.
Spring is for adjusting cut-in, cut-out pressure. I have a small toggle switch by front of comp to turn it off if needed.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Auxiliary Air Compressor Inoperative

Reply #11 –
Take a good look at the switch contacts, if they are pitted, replace the switch, it will only get worse.
The selected media item is not currently available.Bill&Doris 97 U270 36'
University of Parris Island Class of 66
Semper Fi  Build# 5174 MC#17094

Re: Auxiliary Air Compressor Inoperative

Reply #12 –
It might be worthwhile to cycle the pump again and see if that red light is still on.  If you can identify that control box red light with a number contact HWH.  It may be a fault indicator light that will identify the problem.  Just a thought.
Scott & Carol Seibert
2001 42' double slide U320 - Sold
Previous - 2002 36' U320

Re: Auxiliary Air Compressor Inoperative

Reply #13 –
Quote from: Carol & Scott –
It might be worthwhile to cycle the pump again and see if that red light is still on.  If you can identify that control box red light with a number contact HWH.  It may be a fault indicator light that will identify the problem.  Just a thought.
Don had indicated slide is working properly. Problem is with aux air compressor which is not controlled by any HWH control boxes. Believe he just has to solve his aux air comp control problem. He is okay now, he just had to manually control the aux air compressor by pulling control voltage fuse to shut down. If you have a slide problem, this is the best one to have!
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Auxiliary Air Compressor Inoperative

Reply #14 –
After several conversations with HWH, determined that the pressure switch was stuck.  Replaced pressure switch.  Picture is the old switch on the left and the new switch on the right.  The adjustments are noticeably different indicating that the old switch was apparently set at a higher pressure (compressing the spring by turning the adjusting screw 3 turns raises pressure by 10psi).  I emailed James Triana and he told me that Foretravel does not change the pressure.  The compressor does not seem to run as long before shutting off which I think would be consistent with a lower pressure adjustment.  I don't have a way of measuring the pressure.  Can anybody think of any disadvantage to operating at a lower pressure?
Don & Sue
2009 NImbus 38
2020 Jeep Grand Cherokee toad

Re: Auxiliary Air Compressor Inoperative

Reply #15 –
On my 2003 I need at least 75 psi for proper leveling and slide seal inflation. You can put a gauge anywhere in the discharge piping.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.
 

Re: Auxiliary Air Compressor Inoperative

Reply #16 –
"... put a gauge anywhere in the discharge piping" sounds like a good idea but when you crawl into the outside compartment on top of the Oasis furnace in a space that is so tight that you have to exhale deeply to wiggle your way back out, it becomes a BIG job.  The best that I can tell is that the new switch should come on at 8o psi and stop at 110 psi.  I will assume that it is adequate until it is not.

Thanks to all for your help!
Don
Don & Sue
2009 NImbus 38
2020 Jeep Grand Cherokee toad