HWH Air Leveling Troubleshooting

[zmotorsports]

Wondering if anyone has experienced a situation like below that could point me in the right direction.

I have an 03 Dynasty with the HWH air leveling system. When I bought the coach 8 years ago the auxiliary air compressor was seized up and I replaced it along with adding a custom made splash shield to protect the small compressor from the elements as it is placed directly over the steer axle and I can see how road spray could be an issue.

System has worked flawlessly until last week. The wife and I were in a campground and the ground was not even close to being level in the site they stuck us in. After deploying the slides and leveling we were off sightseeing. After a couple of days I noticed one evening that the aux. air compressor was running for what I thought was an extended amount of time. My air system is fairly tight as I check it quite frequently but they all leak to some degree.

I also probably should have left the engine running while I leveled the coach but I didn't feel like starting the coach back up after getting setup so I just leveled up and took off. I didn't notice at the time but my air pressure had dropped off while leveling the coach with the engine not running.

When I noticed that the air compressor was running and the coach was not raising I realized that the air pressure in my tanks were down around 40-ish pounds.

Upon arriving home I started troubleshooting thinking maybe I had an air compressor going out and not putting out enough pressure/volume for the air bags but I don't think that is the case. I built up air pressure with the engine running and the coach levels fantastic just like it should as long as there is air in the system and the engine running, which is due to the more volume the engine driven air compressor can supply vs. the small aux. compressor.

I pumped the brakes enough to drop my air pressure down and once I get down around 40-50 psi and try to operate the air leveling in manual mode, the air bags will not raise at any point under the coach.

Here is my question, isn't the air tank(s) supposed to have check valves to prevent the loss or decrease of air when the air leveling system is functioning? I shouldn't see a decrease in tank pressure when the 12VDC aux. air compressor is trying to raise the low side/end of the coach. I have called HWH and left my contact number with their tech support line but I have not received a call back and to be honest without being a dealer for them I have found their call-backs less than stellar.

Anyone with a similar experience or any insight/thoughts I would appreciate the feedback.

Mike.

[96 Wideglide]

So, The HWH air leveling system doesn't have a seperate air tank that the aux 12V compressor fills?

[MSHappyCampers]

Mike, I had a minor problem with my system and called HWH. It was a couple of days before they returned my call, but the tech was super nice and helpful, and figured out my problem fast! Wish I could help, but don't know enough about the system to advise you.

Good luck, happy trails, and God bless!

[zmotorsports]

Originally Posted by 96 Wideglide

So, The HWH air leveling system doesn't have a seperate air tank that the aux 12V compressor fills?

No separate air tank for the leveling system that is supplied by the 12VDC air compressor.

Mike.

[96 Wideglide]

So, will the aux compressor bring both the front and back tanks up to 120ish psi ?
I have the Powergear/ Valid system, which the aux compressor fills it's own tank. Mabe 3gals. If I drain the tank, it takes about 2min for the compressor to fill it to cut-off, whatever pressure that is. There is no guage either on the dash, or near this tank.

[zmotorsports]

Originally Posted by 96 Wideglide

So, will the aux compressor bring both the front and back tanks up to 120ish psi ?
I have the Powergear/ Valid system, which the aux compressor fills it's own tank. Mabe 3gals. If I drain the tank, it takes about 2min for the compressor to fill it to cut-off, whatever pressure that is. There is no guage either on the dash, or near this tank.

It shouldn't. But that is my questioning. The tanks are actually dropping in pressure but by looking at the system schematics they shouldn't because it appears that there is a check valve in each tank. Again, according to the schematics but systems do not "always" follow the schematics exactly. I know on OTR trucks the wet tanks have check valves to prevent the loss of air through "accessory" systems. That is why I am asking about on the Monaco/Roadmaster, because I don't think my tanks should be supplying air for raising the air bags during the leveling process and I don't recall them doing that in the past. It is one of those things where I probably should have paid closer attention to but got in the habit of hitting the auto-level button and walking away without paying much attention to. I probably wouldn't have thought anything about it other than my compressor was running longer than I thought it should and then I noticed my tank pressure being depleated.

Mike.

[96 Wideglide]

I see. Your thinking the aux compressor should be filling the bags directly, after a valve system controlled by the HWH.
I believe Mike Canter has dug into the HWH system. Hopefully he will see this thread, and be able to help you out.

[Coma]

The pump actually has two parts, the pump, and the dryer. Do you know which Leveling system you have? I have a HWH 680 and Monaco went to a HWH 2000 a few years after, although I believe the pump portion is identical. You can go to Welcome to HWH Corporation. They have wiring diagrams and phone help. Keep in mind Monaco did not always install as directed. My system is supposed to be plumbed after the tanks with a check valve to prevent filling the air tanks with the tiny little pump, instead Monaco plumbed directly into the from tank.

Theory of Operation:

On my system the control wire [#9700] goes to a pressure switch on the output side of the dryer, with a check valve between the dryer and the pressure switch so the switch reads tank pressure. The control wire goes to relay control +. Running current from electrical system is fused near pump and runs to relay. Current flows to pump and dryer from the pump side of relay. The dryer has has a vent solenoid that must close to allow pump to pressurize. When leveling system is satisfied, or tank side pressure switch opens, the big Essex relay opens. This shuts down pump and allows dryer to vent to atmosphere. The check valve on the output side of the dryer, between the dryer and the pressure switch, holds system pressure. The leveling solenoids at the six pack hold pressure in the bags.


Based on my understanding, the 40-50 psi (60psi) is the cutout valve for aux systems. So no pressure to the leveling system. I would guess that the normally open vent valve for the dryer is not closing. It could also be that the check valve has failed in the closed position. This is all assuming the pump is actually putting out pressure. No way to check that except to test it.

This is what I did when mine quit.

My next plan is to add a pressure switch on the pump to keep 100psi in the tank. The pressure switch will run the control solenoid with a diode block to keep from back feeding the control box.

[slickest1]

I don't know this for sure but I think the little compressor only fills the bags through the HWH manifold system (or what ever term you would call the valves and such). When you level the coach it usually drains air from the bags and is controlled by the computer. I would check for a leak in one of the bags or in the airlines between the bags and the valves them selves. Good luck.

[bpotter]

On my 05 Dynasty, when it levels it, it will deplete the air tank if it needs to raise the coach side, front, or back. At first though, it will lower the bags opposite the side that is low so no loss of air on the gauge. With the electric compressor I've seen it pump up the gauge pressure to 50 or so to keep it level. It will take a long time, mine is a new pump so is quiet but wimpy!

-Byron

[zmotorsports]

Originally Posted by 96 Wideglide

I see. Your thinking the aux compressor should be filling the bags directly, after a valve system controlled by the HWH.
I believe Mike Canter has dug into the HWH system. Hopefully he will see this thread, and be able to help you out.

Correct. Based on the HWH schematic that shows a check valve like OTR trucks it should fill the bags directly and not deplete air from the tanks OR at minimum use the tanks until a cutout pressure like OTR trucks use which is usually around 60 psi.

I thought of Mike Canter and considered shooting him a PM but didn't want to bug him and figured maybe he would either see this thread or someone else could spark a thought.

Originally Posted by Coma

The pump actually has two parts, the pump, and the dryer. Do you know which Leveling system you have? I have a HWH 680 and Monaco went to a HWH 2000 a few years after, although I believe the pump portion is identical. You can go to Welcome to HWH Corporation. They have wiring diagrams and phone help. Keep in mind Monaco did not always install as directed. My system is supposed to be plumbed after the tanks with a check valve to prevent filling the air tanks with the tiny little pump, instead Monaco plumbed directly into the from tank.

Theory of Operation:

On my system the control wire [#9700] goes to a pressure switch on the output side of the dryer, with a check valve between the dryer and the pressure switch so the switch reads tank pressure. The control wire goes to relay control +. Running current from electrical system is fused near pump and runs to relay. Current flows to pump and dryer from the pump side of relay. The dryer has has a vent solenoid that must close to allow pump to pressurize. When leveling system is satisfied, or tank side pressure switch opens, the big Essex relay opens. This shuts down pump and allows dryer to vent to atmosphere. The check valve on the output side of the dryer, between the dryer and the pressure switch, holds system pressure. The leveling solenoids at the six pack hold pressure in the bags.


Based on my understanding, the 40-50 psi (60psi) is the cutout valve for aux systems. So no pressure to the leveling system. I would guess that the normally open vent valve for the dryer is not closing. It could also be that the check valve has failed in the closed position. This is all assuming the pump is actually putting out pressure. No way to check that except to test it.

This is what I did when mine quit.

My next plan is to add a pressure switch on the pump to keep 100psi in the tank. The pressure switch will run the control solenoid with a diode block to keep from back feeding the control box.

You explained it correctly. The dryer has a normally open valve that the positive side is paralleled in with the compressor so when the compressor is activated the dryer solenoid/valve is closed thus building pressure. When the 12V + is removed from the relay, the compressor shuts off and the dryer valve is de-energized thus venting to atmosphere. This is the pressure release sound that is heard as the compressor quits.

Verified that all of that part of the system is functioning correctly.

Originally Posted by slickest1

I don't know this for sure but I think the little compressor only fills the bags through the HWH manifold system (or what ever term you would call the valves and such). When you level the coach it usually drains air from the bags and is controlled by the computer. I would check for a leak in one of the bags or in the airlines between the bags and the valves them selves. Good luck.

Bags are not leaking, they are holding pressure properly as are the lines between the bags and manifold(s). The system from the manifolds to the bags all use the same lines up to and including the bags. The air leveling system at the manifold consists of a three solenoids per. Travel solenoid, raise and lower solenoids. There is also a check valve at the bottom of the manifold per side as well.

Originally Posted by bpotter

On my 05 Dynasty, when it levels it, it will deplete the air tank if it needs to raise the coach side, front, or back. At first though, it will lower the bags opposite the side that is low so no loss of air on the gauge. With the electric compressor I've seen it pump up the gauge pressure to 50 or so to keep it level. It will take a long time, mine is a new pump so is quiet but wimpy!

-Byron

So you are certain your system drains the pressure from the tank to raise once the high side lowers to it's lowest level? If that is the case then mine is functioning properly, however, that would defeat the purpose of having the auxiliary compressor. I started thinking maybe there is nothing wrong with my system it just needs to have the tanks pressurized which is why HWH suggests leveling WHILE the engine is running as the engine driven compressor supplies more volume than the little 12 volt auxiliary. But I keep coming back to the purpose of the air compressor and why would it be needed if the tanks had pressure.

You are correct in the sequence of leveling. The algorythm is for the side to side to level first by bleeding pressure from high side first and once that is satisfied it will go on to level front to rear. If the high side drains enough to sit on stops then it engages the pump to raise the low side.

I just for some reason didn't think it was supposed to use the pressure from the tanks and by looking at the air line schematics that I have looked at on HWH's website there appears to be check valves in both wet tanks to prevent this. This is why I am wondering if Monaco/Roadmaster followed HWH's schematic or deviated from it somehow, such as did not install the checkvalves to level quicker as the pressure from the tanks could be used.

I don't think that is the case but I am hoping someone with direct experience with this scenario will chime in as I have been waiting for HWH to call me back for nearly three days now. I may call Monaco tech line just for the hell of it tomorrow and maybe one of their tech guys can tell me if they deviated from HWH's schematic concerning the check valves.

Thanks for everyone throwing their thoughts out. I don't want to come across as being ungrateful to those posting suggestions, it is just I have verified many of these functions prior to posting the question.

Keep the comments coming, maybe it will spark something I haven't thought of or verified.

Mike.

[bpotter]

Mike,
I am going off watching the air gauge on the panel when it is leveling whether I am doing it auto or manual.

Regarding HWH tech, I waited 4 days for the tech guy to call back...(almost forgot what the problem was when he called me)....regarding how to change the level adjustment. I wanted to order a new touch panel today and HWH parts is on a 3 day call back she told me, just to order a part!

Hang in there....they were very helpful when they did call back.

-Byron

[zmotorsports]

Originally Posted by bpotter

Mike,
I am going off watching the air gauge on the panel when it is leveling whether I am doing it auto or manual.

Regarding HWH tech, I waited 4 days for the tech guy to call back...(almost forgot what the problem was when he called me)....regarding how to change the level adjustment. I wanted to order a new touch panel today and HWH parts is on a 3 day call back she told me, just to order a part!

Hang in there....they were very helpful when they did call back.

-Byron

OK, thanks Byron. That is the same thing mine is doing. Maybe that is normal and all this troubleshooting and questioning is for not. I just for some reason didn't think with the compressor running (raise requested) it should draw air from the tanks and deplete the tank's supply.

I will hang in there and wait for HWH to call back.

Thank you for replying back.

Mike.

[Coma]

Originally Posted by zmotorsports

I just for some reason didn't think with the compressor running (raise requested) it should draw air from the tanks and deplete the tank's supply.

I will hang in there and wait for HWH to call back.

Thank you for replying back.

Mike.

FWIW mine works this way. Pump running, tanks will drop pressure till about 55psi to raise low side. Pump shuts down when level is established at about 60psi.