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Topic: Auxiliary Air Compressor (Read 785 times) previous topic - next topic

Auxiliary Air Compressor

Hello, I am having trouble with my auxiliary air compressor. After leveling my unit,  it won't run to keep the tanks full or the unit level. I have checked electrical connections and the F6 fuse in the HWH control box. Is there a circuit breaker that I am missing? After 48 hours my air tanks were under 50 lbs. of air pressure, the HWH leveling system would exhaust air to keep the unit level but would not add air as the compressor would not run.
Thank you,
John Zick
2003 U320
John & Holly Zick
2003 U320
38' Build #6206
FMCA F495485

Re: Auxiliary Air Compressor

Reply #1
John,

Check for excessive mechanical friction of the pressure switch. It can stuck on or stuck off. Lubricant it and move it numerous times to loosen it up.
Jim

2002 U320
Jim Frerichs
2002 U320 42'

Re: Auxiliary Air Compressor

Reply #2
Thanks Jim, I will check that.
John Zick
John & Holly Zick
2003 U320
38' Build #6206
FMCA F495485

Re: Auxiliary Air Compressor

Reply #3
Does the compressor come on when the level buttons are pushed? It is commanded on when you do. Slide key off ignition on and in manual. You also have a fairly large resettable circuit breaker on the hot battery buss. In May be tripped or open. Resettable with red button on side. It's with all the circuit breakers in the basement, but not in the HWH box. The extend/retract key should be in the off position.

Re: Auxiliary Air Compressor

Reply #4
A while back I noticed my Thomas air compressor was not running.  I have a on/off switch on the pump and when I would switch it off and on several times I could hear the pressure switch latching meaning the pump should be coming on.  I tested the voltage going into the solenoid (black looking device at the end of the pump where the wires attach to the pump). I then noticed some burning on the positive wire so disconnected it and found the wire connection at the pump was loose.  Tightened all the connections and things were good for a while.  Then I started having the same issues.  The loose wires had damaged the solenoid (melted/burned it) so I replaced the unit.  Got it from MOT.  Pump runs fine now.  :)  During this process I noticed the purge valve on the water trap will get really hot if the pressure switch is calling for the pump to come on and the pump doesn't come on and the circuit just stays activated for a long period of time. 
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Auxiliary Air Compressor

Reply #5
DSD,
I will take a look at the circuit breakers, are they in the electronics bay? I haven't seen any circuit breakers except for the ones in the bedroom. I will see what I can find.
Wagon Wheels
I will check the wires and make sure I have the voltage there and the wire connections are not loose.
Jim Frerichs
I checked the pressure switch and the "plunger" moves, went ahead and lubed it. Thank you everyone for the suggestions, I will be diving in further today, to see what I can figure out.
Thank you, John Zick
John & Holly Zick
2003 U320
38' Build #6206
FMCA F495485

Re: Auxiliary Air Compressor

Reply #6
DSD,
I will take a look at the circuit breakers, are they in the electronics bay? I haven't seen any circuit breakers except for the ones in the bedroom. I will see what I can find.

Mine are behind white fiberglass panel with 3 wing nuts on it in first bay on drivers side

2000 GV320 4010 build #5712  2019-?
1999 Bounder 2000-2008
Bardstown, KY
🥃The Bourbon Capital of the World🥃

Re: Auxiliary Air Compressor

Reply #7
Mine are behind white fiberglass panel with 3 wing nuts on it in first bay on drivers side
Mine too but think his is located in a different location

Re: Auxiliary Air Compressor

Reply #8
Nope, same place, least that's where mine is. Except my cover is covered with same material as the floors are.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Auxiliary Air Compressor

Reply #9
You don't have a switch on the compressor itself that accidently got knocked to "off" do you?

Also check for an inline fuse on/near that switch if it exists.

Also, go Vikings.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: Auxiliary Air Compressor

Reply #10
Thank you all for the suggestions, the circuit breaker was in the first bay, behind a panel that was covered with same material on the walls being held up with three wing nuts like Tommy D. had mentioned, There was a tag with HWH Comp, Pressed the red button and the compressor came to life. Thank you all for the recommendations and help.
Thank you,
John Zick
John & Holly Zick
2003 U320
38' Build #6206
FMCA F495485

Re: Auxiliary Air Compressor

Reply #11
Do you have a switch on the dash that you don't know what it's for? Might be for the 12VDC pump. Just a thought.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Auxiliary Air Compressor

Reply #12
My aux compressor does not operate either. I currently am at a level gravel pad at the site I am staying at and when I arrived I leveled, no issues, then left the system on with the red light on the HWH always on. I know I have an air leak but.... My brake pressure when from 120 to about  50 in about 72 hours and the coach has ,according to the HWH stayed level although the coach is now resting on the tires all around. I would have thought air compressor would have kicked in to keep the tires off the coach but it has not  My compressor does not have a fuse in close proximity to it that I can find and the breaker in the bay looks ok. Suggestions?  Is this normal for the coach to rest on the tire instead of levels above them?  On another note the coach just looks "funny" being that low.... So much the air step is almost on the ground!

Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Auxiliary Air Compressor

Reply #13
A quick test is to turn the ignition on, press the AIR button once to turn on the HWH system and then press one of the up arrows at one of the corners.  If you have a yellow light at one spot, that's the low point, so press the up arrow there.  When raise is commanded, the HWH pump should run despite the pressure switch.  Does it?

If not, do you have 12V at the hot wire going into the solenoid?
Keith
2003 U320 38' #6197

Re: Auxiliary Air Compressor

Reply #14
When I push the auto level twice the high side will rest on the tires before raising the low side. Don't see any issue with that.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Auxiliary Air Compressor

Reply #15
Mine does the same as Chuck, It keep lowering until it hits a tire. I have never heard
my compressor running but it stayed level for almost 2 weeks. I know my compressor
works as used a jumper wire to get it going. As it has never been an issue I haven't looked
into it any further.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

 

Re: Auxiliary Air Compressor

Reply #16
I'm not sure how much different your system is than mine, but with the air light on solid, the system is active but not in auto-level mode.  On mine, you press the air button twice and it will level.  Once level, the air light goes to flashing very quickly and much dimmer, indicating the mode to maintain level.  At that point, if it determines one area is high, it will dump air.  If one area is low, it will add air AND the pump will run, regardless of the pressure in the tank.
Keith
2003 U320 38' #6197