Today, I went to storage and noticed that the small compressor came on. I am not sure why this needs to run when the coach is stored so I pulled the fuse. The slides are in and hooked to 30 amp just to keep plugged in. Noticed the air pressure was still at 90 on both front and rear. Guess the small compressor had been keeping the air up. Have the 12 volts off at door. What is the small compressor supposed to do when the coach is in storage???? I have never pulled the fuse before. So this is new?? Can someone tell me what is right or wrong?? Tks DAN
If not actively raising for leveling, it keeps the slide bladder air tank pressured up.
Michelle
Dan, I had the same issue when we recently had a couple leaks in the system. It was running often until I found and fixed the leaks. Through the forum and seeing it for myself I learned that even with the fuse pulled and the 12 volt's off the compressor is wired to still be able to come on when the leveling system requires it.
Michelle: Is it necessary to keep slide bladder pressure up when in storage??. Just never noticed it coming on before when in storage and if for some reason it decided to run constantly, by pulling the fuse this will pervent a burnt compressor>>>(if it is not needed) Tks DAN
Dean: I have the leveling system off. Will this prevent it from coming on??? DAN
It should. But if the slide bladder requires air it may still come on. Other's may know which one but I know one or both of those system's will activate it without the fuse in. I was surprised when mine came on with what I thought was no power supply.....
The small 5 or 10amp automotive fuse that's close to the pump will disable the compressor from coming on when the slide air tank calls for it to come on.
It would still come on if you have the system in active level mode (thats another fuse) since the compressor also feeds the front and rear air suspension manifolds so you can stay level with the engine off.
It may also come on if you have your dash aux pump (or whatever that switch is labeled) on, since that interlocks the small compressor it with the front/rear air brake tanks.
I think the 90 you saw was just the slide air tanks, thats the typical cutoff. If you throw the dash switch you would see that drop quickly as that would then allow the slide tank to feed the front/rear brake tanks (and cause the small compressor to come on), at least thats how it works on our coach. I'm not certain how the dash or driver info center gets its air pressure numbers to show, seems different while the engine is off vs on.
Do you need the slide bladders inflated? .... depends where you store it, if inside or well covered maybe not, even if they go to zero air pressure they will probably still seal enough to keep the bugs out. If outside and they go flat, you could allow for water penetration.
Hi guys,
Speaking of the DC air compressor...does anyone know the part numbers and where to buy on line, etc:
- the plastic bowl for the exhaust filter
- the normally closed pressure relief solenoid assembly
Jim 2002 U320
We bought ours from FOT Photo upload - HWH aux compressor filter bowl replacement (http://www.foreforums.com/index.php?topic=14596.0)
About $55 for one of them, $165 for the other (after MC discount, last year's prices).
5Z610 DESICCAN (the expensive one, can't buy just the bowl)

RAP90539 bowl, poly (the cheaper one)

I will have to look for the p/n for the N/C exhaust valve....
Michelle
Checking with Steve, if you're talking about the water trap exhaust valve that you hear open when the pump stops - it's normally open, not n/c. RAP6354. Also purchased from FOT (and MOT). Price anywhere from $100-150. We have replaced it a couple of times (and rebuilt it, as has George Hatfield):
HWH Solenoid Valve Rebuild (http://www.irvblog.com/foretravel%20projects/HWH-Solenoid-Valve-Rebuild)
Michelle
Quote from Steve,
Where is this other fuse?
Thanks,
Hi Dan. Maybe this will help just a little. Keith Davis told me to store in Travel mode to avoid that auxiliary compressor from coming on and trying to level. The thinking....if you store in level and there is a leak, the compressor would likely just burn up trying to overcome the leak.
Episode: Peter found the compressor running while body work is being done at Xtreme. It was very very hot. Peter and Greg unplugged the fuse at the compressor to disable it. On this coach there is a wire with an inline fuse hanging down (yellow as I recall) THey just removed it. That shut it off, I think totally? However, others raise points about how that compressor might still run and I have not addressed that. But for me, what they did seemed to have worked until MOT can get the coach back from Xtreme and determine if there is/was a bladder leak or air bag (level) problem as I suspect or other aspects, such as leaks around some seals.
If Peter logs on he might better define the location of the fuse. I would take a picture for you but the coach is locked up at Xtreme this weekend. Mike
Mike: Tks for the info. The fuse was hanging down and when removed the air went off as well as the compressor.
The compressor had just came on and this was the first time I had noticed it coming on while the coach was in storage. I store in travel mode. So this should keep the compressor idle. We are planning a trip to Branson next week. Always stayed at the ABC when in Branson but this time I am going to try the KOA . The last time at the ABC it appeared to have a lack of attn and dog poop everywhere plus the gravel tracks into the coach. Will be in Nacogdoches on Monday. DAN
The fuse is right where the pump is located in Mike's coach which is located in the middle storage compartment up high toward the front of the compartment. Dick, your 2003 may be located in another location. Steve & Michelle can help you locate the pump's fuse better.
Peter
Dan,
The compressor operation in your coach may be just normal. In Dick's coach, I listened for a while to make sure it would shut off. It did not and the compressor was extremely hot. So Pulling the fuse was the only alternative so as not to burn up an expensive compressor.
Peter
Trip update and auxiliary compressor function, level malfunction.
1. Coach parked unlevel, blocks under front tires to help raise front. Level system then activated.
2. Dash air gauges dropped 35 psi in five hours. In time coach listed to driver side.
3. What I have heard.....still working on this
A. The auxiliary compressor keeps the bladder filled, necessary. Keep that function running if you cannot chance rain or pests entering if the bladder deflates.
B. That compressor may or may not be connected to a small auxillary air tank that works to leveling or it may work to fill the large main tanks that give air to leveling
C. If it goes only to the large tanks, the small compressor may really struggle and you need to crank the engine to fill these.
D. I got the coach mechanically more level so the air bags are not so extended, one tire in a dump type position. That greatly slowed air loss to about 60 psi in 48 hours. Level is maintained,
E. I do not think the aux compressor comes on as the psi drops but I can trigger it to turn on by venting a little air from one of my three front vent valves.
F. At this point though the psi is really too low to fill the tanks with the auxillary compressor. I crank and fill to 125.
G. The fact that I have three front valves suggests that I may have the small aux tank for keeping level, a goofd thing if true, but I may have a check valve failure letting air move such that the aux compressor has to try to do too muc.
H. I now measure to one-eighth inch the fender distance to a point on the ground plus I keep a two foot Level on the dash to understand behavior when it leaves level (which tire changing how much if level changes).
Until I get back to FOT or MOT I will not fully define what is happening. In the meantime I hope this helps someone, food for thought.
Mike
The 3rd air tank is for your bladder, optional tank flush and auto awning.
"The 3rd air tank is for your bladder, " Quote-Barry Beam
Gosh darn it I have to get one of those things to help me sometimes!!
John H
How about going underneath and use a soap solution (party bubble solution really works well) spray bottle to see if you have a airbag/hose/fitting leak somewhere underneath? Must be at least 100 opportunities for a leak to occur down there.
Pierce
Mike,
When the HWH controller wakes up to recheck level, does it need to exhaust any air to achieve level?
Coach listing - just front, just back, or entire side (can you tell)?
Does the driver's side air bag(s) measure less distance between plates after listing or instead does the passenger side air bag(s) show an increase in height? Don't automatically assume appearing lower means less air; it could be higher on passenger side due to air adding to the bag on that side.
As we learned in our coach, leak through a raise solenoid valve seat (due to damage, debris, etc. causing poor seal) can allow air leak into an air bag, causing level issues and odd listing.
Michelle
Michelle, i have not heard an exhausting of air as I would expect. None.
The coach seemed to become lower on the passenger side based on the level on the dash and visual observation, i.e. that side was lower than the driver side.
I have been measuring the distance from ground to the fender in a constant method. Data collection is not for a complete cycle of being necessary to crank the engine to build pressure. However, in the past 30 hours, the gauges have gone from 125 psi to 100 psi.
Driver front fender has raised .75 inch and driver rear has raised 1.25 inches.
Passenger front is unchanged and passenger rear has raised .70 inches.
So driver side has raised more than the passenger side which has raised a bit on the back.