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Topic: Compressor not coming on in "auto level" mode (Read 537 times) previous topic - next topic

Compressor not coming on in "auto level" mode

Coach is park, in "auto level" mode, had no issues levelling itself when I parked it. I'm still leaking down in one corner and expected the air compressor to come on to adjust but it has not. I can adjust the coach in "manual" mode, so the compressor is working just fine. It must be an issue somewhere between the HWH brains and the compressor, or the HWH brains and the mercury switches under the kitchen sink. Is there any low hanging fruit to look for?
1987 Grand Villa ORED
2001 U320 4010

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

Re: Compressor not coming on in "auto level" mode

Reply #1 –
Wish I could help, but welcome to 2001 Foretravel's electron hell.  Mine does the same thing, and you have a lot less leaky air system than I.  The only thing on mine that holds air is the HWH air tank....4 weeks is the average, and my airbags now can stay where manually set for a few weeks or more.  Everything else is like a kid's birthday party balloon.

On a serious note, I put 2 coach bucks into MOT's coffer AFTER the slide seal replacement to fix this exact thing, and they were stumped.  Corporate knowledge of these sophisticated coaches is disappearing.

Best of luck, Elliott.  Hopefully someone will chime in and help in earnest, but I'm pretty confident that you will figure it out for the rest of us, right?!!

Woody.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Compressor not coming on in "auto level" mode

Reply #2 –
Quote from: Pyolet –
but I'm pretty confident that you will figure it out for the rest of us, right?!!
I will be eligible for HWH employee of the month by the time this coach holds air how I want it to.
1987 Grand Villa ORED
2001 U320 4010

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

Re: Compressor not coming on in "auto level" mode

Reply #3 –
It will DISCHARGE air to bring  the high side down if the tank pressure is above 80 psi. When it goes BELOW 80 lbs the aux compressor will come on and add air to the low side. So.....if your gauge shows >80 psi, it ain't gunna come on.
1994 U280, Build 4490
Deming, NM.

Re: Compressor not coming on in "auto level" mode

Reply #4 –
Elliott,

I don't know what HWH system you have, but in general the Auto Level system works in two stages.  Each time the system "wakes up" it looks for yellow lights on the panel (indicating a out of level condition).  Initially, it will lower the high side (or end) as required to extinguish the yellow light(s).  Eventually, it will reach bottom of travel on the suspension.  If it still sees a yellow light, it will try to add pressure to the bags as required to extinguish the light(s), using air in the storage tanks until depleted, and then the aux compressor.

SO, if you park the coach when it is at normal travel height, it may be quite a while before you ever hear the aux compressor come on.  As the coach goes out of level, you'll occasionally hear the hissing noise when the HWH system releases pressure.  Some people say this is the coach "marking it's territory"...a humorous analogy to the habits of some male animals.  How soon you reach the point where the aux compressor runs depends on how tight or leaky your air system is.

If your coach goes obviously out of level, but you never see a yellow light on the control panel, then you have a problem with either the level sensor or the wiring between it and the control panel.

If you want to test your aux compressor, wait until the pressure in the air system gets down below about 70-80 psi (as mentioned by Twig) and then try to use the "RAISE" button on the HWH control panel.  The aux compressor should come on as the system attempts to comply with your request.  If it does not run, then you either have a compressor power supply fault, or lack of communication between the control panel and the compressor.  EDIT:  I see you already covered this test.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Compressor not coming on in "auto level" mode

Reply #5 –
Thanks guys.

 How does the HWH system know there is less than 80 psi in the tanks? The pressure switches on the manifold?
1987 Grand Villa ORED
2001 U320 4010

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

Re: Compressor not coming on in "auto level" mode

Reply #6 –
Quote from: Elliott –
How does the HWH system know there is less than 80 psi in the tanks?
System pressure switch on rear 6-pack manifold.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Compressor not coming on in "auto level" mode

Reply #7 –
Quote from: Chuck & Jeannie –
System pressure switch on rear 6-pack manifold.
That's my leading suspect then because the rig is visibly going out of level and pressure dropping to 70 psi.

Actually, first suspect is that switch I put in the bathroom. My HWH panel only works when the ignition is on so it's possible my aux compressor is able to auto/ manual level when I'm monkeying with it because it's getting power from the ignition side of the solenoid. I put it in auto mode then bypassed that switch so I know it has power with the ignition off. Have to wait now and see if it keeps itself level over night.

Pretty sure I had these symptoms before I put that switch in though, but can't completely remember
1987 Grand Villa ORED
2001 U320 4010

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

Re: Compressor not coming on in "auto level" mode

Reply #8 –
Don't know what's going on, but I'm not complaining.

Four months into a six month trip, and my compressor has stopped cycling. But the coach is staying perfectly level. All is good.

For a while it was cycling every four hours and re-leveling.  Later it was cycling every six hours but not re-leveling.

I'm guessing some dirt in a valve got blown out of place.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Compressor not coming on in "auto level" mode

Reply #9 –
Well, it leaked down overnight again. The compressor is definitely getting power even with the ignition off. I was able to put it into auto level mode, and then shut the ignition off and it kept leveling.

How do I determine which model HWH system I have?
1987 Grand Villa ORED
2001 U320 4010

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

Re: Compressor not coming on in "auto level" mode

Reply #10 –
So I think Twig is on to the culprit.  The solenoid I put on the airline before my leaky step/slide cover came in handy.

I levelled the coach, turned that solenoid on, and let the air leak out of the front tank. The compressor kicked on automatically during the next HWH cycle. So, that tells me it's not getting below 80psi or the pressure switch is wonky.

I think my solve here is going to be to find the leak I have up front. I could just use manual levelling too but I want my damn auto levelling.
1987 Grand Villa ORED
2001 U320 4010

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

Re: Compressor not coming on in "auto level" mode

Reply #11 –
Quote from: Elliott –
How do I determine which model HWH system I have?
See page linked below.  Scroll down the page to find your specific system.

https://www.hwhcorp.com/ml17785_01_nom_pr_lesy.pdf

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"
 

Re: Compressor not coming on in "auto level" mode

Reply #12 –
This is the one for the 2001 coaches.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN