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Topic: HWH leveling system continuously pushing air (Read 663 times) previous topic - next topic

HWH leveling system continuously pushing air

On my 1994 U300, the HWH System is continuously pushing air out through the height valve discharge. I feel like one of the leveling plungers is stuck or not functioning properly. The airbags inflate and seem to hold air as they should. However, air is continuously discharged from the height valve exhaust port. Any ideas???  Could it be electrical or computer??? :-X
Front system only.
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Gerry & Brenda
CHARLOTTE HARBOR, FL
1994 Grand Villa - # 4466
U300 Unihome - 6V92 Detroit
4 speed Allison - Jake Brake

Re: HWH leveling system continuously pushing air

Reply #1 –
Likely the valve itself. You could try tapping on the valve to see if the valve will seat. Regardless, I would replace the valve.  If the valve was a pricey part I might would do differently but if it doesn't fix the issue you will have a spare to carry with you. Said this because tracing a "possible" electrical issue will be a time consuming process. jmo.
Dub McBride 1996 270

Re: HWH leveling system continuously pushing air

Reply #2 –
Are you talking about one of the 6 hwh 6 pack valves, or one of the ride height valves located in the center front and on rack side in the rear?
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: HWH leveling system continuously pushing air

Reply #3 –
Quote from: bbeane –
Are you talking about one of the 6 hwh 6 pack valves, or one of the ride height valves located in the center front and on rack side in the rear?
The ride Height valve is working properly. I actually replaced it, and I still have the problem. I think my problem is in the front six pack. I am to the point where I would consider bypassing the front six pack and diving back to Florida not being able to level for that trip.
The selected media item is not currently available.
Gerry & Brenda
CHARLOTTE HARBOR, FL
1994 Grand Villa - # 4466
U300 Unihome - 6V92 Detroit
4 speed Allison - Jake Brake

Re: HWH leveling system continuously pushing air

Reply #4 –
Quote from: Gerry Vicha –
The ride Height valve is working properly. I actually replaced it, and I still have the problem.

Is the new ride height valve set correctly?

See Chuck's excellent explanation here More on ride height??? which includes a link to the wiki article Haldex Height Control Valve (HCV) Troubleshooting Guide
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: HWH leveling system continuously pushing air

Reply #5 –
Quote from: Gerry Vicha –
...air is continuously discharged from the height valve exhaust port.
Front system only.
Gerry,

So far in this discussion, I am still not clear on where exactly the air is being vented.

Is the air being vented from the exhaust port on the bottom of the front Height Control Valve?

The front 6-pack has two exhaust ports.  Is this where the air is being vented?

In photo below of front 6-pack red arrows point to exhaust ports.

If the air you are talking about is being discharged from the bottom exhaust port of the front height control valve, then this has nothing to do with the front 6-pack.  It is not related to anything electrical or computer controlled.

When the front height control valve is in operation, the HWH leveling system is turned off.  The only way air would be discharged continuously from the height control valve exhaust port would be if the valve control rod is not in the horizontal position.  This would be corrected by adjusting the control rod back to the horizontal position.

If the height valve control rod is in the correct horizontal position, and air still vents out the bottom exhaust port, then the valve is faulty.

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: HWH leveling system continuously pushing air

Reply #6 –
I misunderstood.
Dub McBride 1996 270

Re: HWH leveling system continuously pushing air

Reply #7 –
The attached file I don't think is your vehicle but the front should be exactly the same.  There are two travel solenoids active when travel is selected.  When these two valves are closed the height control should not exhaust since it will not be receiving air from the air bags. If you have installed a new valve you either have it plumbed wrong or as said above the level is in the wrong location.

2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: HWH leveling system continuously pushing air

Reply #8 –
This sounds exactly like what happened on or coach except it was the tag lift plunger in the 6 pack.  We were worried the leak was greater than the air pump could provide(not but we were worried about braking).  We put a 1/4 npt plug in the exhaust port and
drove home 1000 miles with no problem.  Rebuilt the 6 pack at home and problem went away.
Jerre and Kathy Griffin
2003 U320 4220 Special
Build # 6207
2022 RAM Laramie 4X4 EcoDiesel
2002 Country Coach Magna 37 Tag- Forever Coach-Died in fire 7/23
1997 Country Coach 32 Intrigue-No slides-Wonderful

Re: HWH leveling system continuously pushing air

Reply #9 –
I have talked to Gerry.  His "continuous air discharge" is coming from the exhaust port on the bottom of the front height control valve.  It has nothing to do with the front 6-pack exhaust ports.

As turbojack has mentioned, when the coach is in Travel Mode the HWH Leveling System is turned off, and the travel solenoid valves on the front 6-pack are open.  This allows free air flow into and out of the front air bags.  The travel solenoid valves are passive - they do not "regulate" flow, but are simply held in the "open" position to facilitate air flow in either direction.

When the coach is not in Travel Mode, the travel solenoid valves on the front 6-pack are closed.

In Travel Mode, the front height control valve regulates the flow of air pressure into and out of the front air bags.  The height control valve is connected to a constant "supply" of air pressure.  The lever arm on the valve opens and closes air flow ports inside the valve body.  The lever arm has three positions: Intake, Exhaust, and Neutral.

Intake directs "supply" air pressure to flow from the height control valve, through the open travel solenoid valves on the 6-pack, and into the air bags.

Exhaust allows air pressure to return flow out of the air bags, through the open travel solenoid valves on the 6-pack, back into the height control valve, and out the bottom exhaust port.

Neutral stops the flow of air pressure through the height control valve in both directions.

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: HWH leveling system continuously pushing air

Reply #10 –
Sounds to me like a bad valve, or possibly installation issue. Not much other possibilities.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: HWH leveling system continuously pushing air

Reply #11 –
Quote from: Chuck & Jeannie –
Gerry,

So far in this discussion, I am still not clear on where exactly the air is being vented.

Is the air being vented from the exhaust port on the bottom of the front Height Control Valve?

The front 6-pack has two exhaust ports.  Is this where the air is being vented?

In photo below of front 6-pack red arrows point to exhaust ports.

If the air you are talking about is being discharged from the bottom exhaust port of the front height control valve, then this has nothing to do with the front 6-pack.  It is not related to anything electrical or computer controlled.

When the front height control valve is in operation, the HWH leveling system is turned off.  The only way air would be discharged continuously from the height control valve exhaust port would be if the valve control rod is not in the horizontal position.  This would be corrected by adjusting the control rod back to the horizontal position.

If the height valve control rod is in the correct horizontal position, and air still vents out the bottom exhaust port, then the valve is faulty.

Well, here is the "Final Report".  The above post helped answer my problem.  Evidently, at some time recently, I lowered the coach all the way down onto the  "Bottom Blocks." When I did that, it must have caused the "Height Adjustment Rod" to move from the original set location, thus not allowing the coach to raise to the proper ride height. Because the actuator rod was out of position, causing constant air flow from the height valve.  I overthought my problem and installed a new height adjustment valve that was not needed. 
"If the air you are talking about is being discharged from the bottom exhaust port of the front height control valve, then this has nothing to do with the front 6-pack.  It is not related to anything electrical or computer controlled."  Thank You Chuck and All for the Help
The selected media item is not currently available.
Gerry & Brenda
CHARLOTTE HARBOR, FL
1994 Grand Villa - # 4466
U300 Unihome - 6V92 Detroit
4 speed Allison - Jake Brake