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Topic: HWH Air Seal Manifold Assembly Leaking (Read 2137 times) previous topic - next topic

HWH Air Seal Manifold Assembly Leaking

Extended slides and after 12volt pump continued to run after several minutes discovered air was escaping from the vacuum chip (half moons on each side of the rectangular black plate is what they are referred to in HWH Manual) on each side.  The manifold assembly is for the bedroom seal so unable to inflate.

On the manifold there are three valves.  12 volt normally closed air valve, 12 volt 3way air valve and a vacuum switch normally open.  Also the air pressure regulator is on the manifold. 

Help in what would cause the air leaking continuously from the vacuum chip would be appreciated.
Gary Mauck
Deerfield Beach, Fl.
2005 U320 40' PBGB

"Elks Care, Elks Share!"

Re: HWH Air Seal Manifold Assembly Leaking

Reply #1 –
Gary,

I have no direct experience with your version of HWH system (ours is much simpler).  I'm not clear on what you are referring to as "the vacuum chip".  However, from past reading on our Forum, I learned that the black rectangular thing on your manifold (marked PIAB) is a vacuum pump.  You might find some helpful info in this thread:

Air system parts

I have also found a reference to this device on another forum which says it is normal for air to be escaping from this device while it is in operation.  Here's the quote:

"BTW, the PIAB vacuum pump mounted on the manifold does exhaust quite a bit of air while doing it's job. It's a no-moving part, simple device that uses compressed air to draw a vacuum (there's a steady hissing sound), so it's not unusual to hear the 12V compressor run while sucking air out of the seal."

And here's the reference source:

Air Valve Leak  (First page only - after that they digress)

I'm not sure if this helps answer your question, but thought it might help.  Other members with your same system will undoubtably respond with more pertinent advice.

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 Air Seal Manifold Assembly Leaking

Reply #2 –
Thank you Chuck for the links.  HWH refers to the indented half circles on each side or the plate marked PIAB as vacuum chips. 

When I turned the key to extend the bedroom slide the seal deflated, slide went out and when I turned the key off the seal inflated. Now the pump runs continuously because air is constantly escaping from the vacuum chips so I'm assuming the system is trying to keep the seal inflated. 

While trouble shooting I had pulled the fuse know I have the valve shut off to the manifold so the pump is no longer running but the bedroom seal is not fully inflated.  I'm able to slide a credit card between the seal and coach body.
Gary Mauck
Deerfield Beach, Fl.
2005 U320 40' PBGB

"Elks Care, Elks Share!"

Re: HWH Air Seal Manifold Assembly Leaking

Reply #3 –
I'm not contradicting you, but I'm feeling like there is a "terminology" misunderstanding here.  Look at the diagram linked below.  It looks to me like the term "chip" refers to the complete vacuum pump device.  In the diagram, the little half-moons on each side look (to me) like the connection points (tubes?  ports?) between the pump and the manifold.  (Scroll down to the bottom of the diagram).

Once again, this may not help you fix your problem - I'm just trying to clarify the actual location of the leak.  You might try removing the PIAB pump, take it apart, see what it looks like inside, and how it seals to the manifold.  Many HWH problems can be traced to O-ring leaks...fixed with a simple replacement.

http://www.hwhcorp.com/mp79071a-b.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: HWH Air Seal Manifold Assembly Leaking

Reply #4 –
My '03 did the same thing one time, believe I just recycled the key switch.
Dave W. (AKA Toyman )
'03, 270, 36', Build 6095, Pulling whatever I hook it to.

"Don't cry because it's over. Smile because it happened."
Dr Seuss

Re: HWH Air Seal Manifold Assembly Leaking

Reply #5 –
Chuck the diagram you attached shows the half moons as exhaust ports, the operators manual I have had me thinking they were included in what they labeled the PIAB vacuum chip.  They did not Id them as exhaust ports (duh I should have known that) which is where the air is constantly escaping from if I allow the 12 volt pump to run. 

Yesterday I Called HWH tech support, they were returning calls from people who called on the 17th so I figured it will be a week or so before they are able to get back with me.

Spoke with tech support at PIAB today and he feels it is highly unlikely the vacuum chip is the cause of the problem.  Went over the components of the manifold block and he felt the 3-way solenoid valve which as the air seal to the vacuum chip which is normally closed has failed bcause air is continuously escaping.


Gary Mauck
Deerfield Beach, Fl.
2005 U320 40' PBGB

"Elks Care, Elks Share!"

Re: HWH Air Seal Manifold Assembly Leaking

Reply #6 –
Quote from: Gary & Jeannie –
Spoke with tech support at PIAB today and he feels it is highly unlikely the vacuum chip is the cause of the problem.  Went over the components of the manifold block and he felt the 3-way solenoid valve which as the air seal to the vacuum chip which is normally closed has failed bcause air is continuously escaping.
OK, this makes more sense to me.  A leaking valve is definitely something that can be repaired, IF you can get the parts.

One of our members recently had a problem similar to yours.  Link below.  He successfully rebuilt the valves on his slide manifold.  You can read about his experience.  If you need any clarification, just PM him.  Rich is a good guy - he won't mind trying to help you.

HWH Slideroom Bladder Manifold repair/rework
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 Air Seal Manifold Assembly Leaking

Reply #7 –
@Gary & Jeannie,

If you decide to try to rebuild the valves on your slide manifold, you might want to invest in one of the HWH kits from Tom McCloud.  Each of these kits contains the parts required to rebuild 6 of the standard solenoid valves on a HWH 6-pack manifold.  As you read in the post linked above, the plungers, O-rings and springs in these kits could also be used to rebuild slide manifold valves.  (The plunger in the "3-way" valve would have to be reused)

Tom has just posted that he has some kits available.  If you are interested, contact him via PM for more info.

Replica HWH Plungers Redux
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 Air Seal Manifold Assembly Leaking

Reply #8 –
Chuck, thank you for bringing to my attention Rich's post.  Sounds like there is a good chance I can fix my problem rather than having to purchase a new complete manifold.  Hoping the PIAB tech is right that chances the vacuum chip is the cause are very slim.

I purchased 2 of the HWH kits from Tom a while back.  Tomorrow we are heading home from a Foretravel rally so Monday I plan on rebuilding both valves.  If it works the dollar savings will be substantial.  Thank you for all your help, I'll report back on the outcome.
Gary Mauck
Deerfield Beach, Fl.
2005 U320 40' PBGB

"Elks Care, Elks Share!"

Re: HWH Air Seal Manifold Assembly Leaking

Reply #9 –
Hi Gary,

I'm thinking of a problem with the 3-way solenoid too:
1. Mechanical: valve stuck on the deflate position.  You may be able to fix it with your kit.
2. Electrical: bad coil.  No longer energize or move the plunger anymore.

Please share what you find out.

Thanks,
Michael
Ex 2001 U295

Re: HWH Air Seal Manifold Assembly Leaking

Reply #10 –
Arrived back home Sunday afternoon and yesterday Jeannie spent a good amount of time cleaning the interior.  After ever trip she cleans everything from top to bottom, almost take my shoes off when I go in it after she's done.  So I decided to wait and rebuild the valves today.

This morning I went over to Ace and bought a tube of Super Lube for the rebuild of valves.  Started the coach to run the slides and before bringing in the bedroom went in the electronics bay to turn the shut off valve back on to the bedroom slide, 12 volt pump came on and air was blasting out of the exhaust ports.  Brought the slide in and went out expecting air to be escaping from the manifold and 12volt pump to be running continuously.  It has know been over 4 hours and the 12 volt pump has not run once, no air is escaping and the slide seal is fully inflated.

Gary Mauck
Deerfield Beach, Fl.
2005 U320 40' PBGB

"Elks Care, Elks Share!"

Re: HWH Air Seal Manifold Assembly Leaking

Reply #11 –
Isn't magic wonderful!  Sometimes things just fix themselves.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: HWH Air Seal Manifold Assembly Leaking

Reply #12 –
Gary, I think something was blocking the exhaust port keeping it open.
John M.
John & Carm Morales

"We travel not to go anywhere, but to just go.  We travel for travel's sake.  Our great desire is to move."
 

Re: HWH Air Seal Manifold Assembly Leaking

Reply #13 –
Rich, after reading your detailed manifold repair/rework post I felt confident I would be able to fix my problem.  Especially the part regarding being able to utilize the spring and o rings from the HWH plunger kit in the three way valve.  As John mentioned I'm also thinking something was causing the exhaust port to remain open.  The only thing I can think of by running the slide in and out several times it was freed up.  I practice the 5 second rule so I think in the future I'll practice operating the air system several times to correct the problem.

I am still on the HWH call back list, today they were working on calls from the 21st.  Hoping to get a call back in about a week so I can ask them if the likely hood of the vacuum chip failing is almost nonexistent and the manifold valves would be most suspect.  I'll report back on what I find out.

Gary Mauck
Deerfield Beach, Fl.
2005 U320 40' PBGB

"Elks Care, Elks Share!"