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Topic: HWH Slideroom Bladder Manifold repair/rework (Read 2357 times) previous topic - next topic

HWH Slideroom Bladder Manifold repair/rework

OK, this is going to be a little long.  If anybody has more knowledge or corrections to my post, feel free to jump in. 

My 12V compressor was running about every 2 hrs and I wanted find the leak and fix it so it ran much less frequently.  I isolated the problem to the slideroom bladder manifold, located on the rear wall of the basement on the driver's side of the coach.  See picture #1.

From what I can figure out from observation on how it works:

After you bring in the slideroom, when you turn OFF the slideroom control key, one valve fills the bladder (with pressure regulated air) and then closes.  Then when you want to extend the slideroom and turn ON the slideroom key to deflate the bladder, the first valve opens and an additional valve opens to bring a venturi online to suck down the bladder.  On my coach, there appeared to be a leak (when OFF) in the second (sucking) valve. 

I deduce this because:

1. if I turn off the manual isolation valve for the manifold, the bladder remains inflated and the compressor does not run excessively (every 1-2 hours)
2. therefor, the fill valve works and does not leak but the deflate valve works but does leak overtime.

I was hoping that the "HWH Replica Plungers" would fit the slide out manifold valves as well as the suspension 6-Pack.  I thought I could rebuild them and solve my problem.  HWH will do a manifold rebuild but I was quoted Not More Than $434 depending on parts, etc.  I have not priced an individual solenoid but have seen older estimates of about $100. 

See picture #1.  If I turned off the supply line (black valve on the right), the bladder retained air and the pump would go many hours before running.

As far as I have been able to figure out, the components on the manifold are:

1. upper left-a solenoid valve labeled "3-way"--This is the valve to fill the bladder.  This valve has an air line in the top but I hoped it would use the same plunger, etc as the airbag 6-Pack. 
2. upper right-a rectangular unit that is the venturi for deflating the bladder labeled "PIRB"
3. bottom center-a pressure regulator
4. bottom right-a solenoid valve labeled "exhaust"--this valve is just like the valves in the airbag 6-Pack 

There is also an interesting component in the supply line on the right side in the picture.  There are 4 pieces (from left to right) in the brass stack:

1. a 1/8" Male to 1/4" Female adaptor
2. a 1/4" Male to 1/4" Male piece that appears to be a check valve.  See pictures #2 and #3 for a look at both ends of this piece
3. a 1/4" Female to 1/4" Female shutoff valve (this has shown a small leak around the stem in some positions in the past)
4 a 1/4" Male to plastic tubing connector

It looked to me that I might get lucky and be able to rebuild the solenoid valves like the thread on the 6-Pack valve rebuild.  I therefore jumped when the chance came up last week to order another 6 plunger rebuild kit.

With plungers in hand, I removed the manifold from the coach and moved to the work bench.  I removed the "exhaust" valve (see picture #4) and it was the same as the 6-Pack solenoid valves.  I used a set of the new o-rings, spring, and plunger (see picture #5) from the kit I bought and rebuilt the valve. 

Then I took the valve labeled "3-way" apart (see picture #6).  It was not the same in several respects.  I knew it had an air line in the top before I started but the plunger is also different (see picture #7).  It has 4 grooves running the length of the plunger instead of two.  So I installed a new spring and o-rings and reused the original plunger.

I also replaced the manual shutoff valve and added a pressure gauge to the supply side of the shutoff valve plumbing.  I left the component that looked like a check valve in the same position in the stack when I put it back together.

I put it all back together and reinstalled and pressure checked my fittings.  See picture #8.  This reminded me why I hate working on plumbing--house, coach, water or air, it doesn't matter.  After tracking down and finding several leaks, I'm now reasonably happy with the results.  I'm still doing some pressure/leak testing but my leak down time seems to be over 24 hrs between 12V compressor runs and the small remaining leak(s) appears to be somewhere else in the system upstream from the manifold plumbing I worked on.

With the pressure gauge in the system, I can see that the 12V compressor will turn on when the pressure drops to about 77 psi and will turn off when the pressure hits about 102 psi.

I also found something else that I did not expect.  Several years ago, I installed a switch in the 12V compressor power line so I could turn it off to refill the desiccant without having to pull the fuse.  This switch will turn the compressor on/off when the slideroom bladder is being filled or deflated.  I found that the compressor also gets power from another source.  With the switch off, the compressor will still come on when the leveling system is calling for air.  I'd be interested in any comments on this little discovery.

Thanks to many who have gone before on the Forum for their knowledge, especially Chuck for his 6-Pack rebuild thread and his HWH Replica Plunger procurement efforts.

Rich

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #1 –
Excellent investigative report, great photos...should be very helpful to those members having the same slide system.  It's cool that the rebuild kit can be used for at least one of the solenoid valves.  The old (2-groove) plunger you removed didn't look to be in real bad shape, but still nice to have a fresh one to install.

About the dual power circuit to HWH pump.  Must be unique to the coaches with both air leveling and air-controlled slides.  Does your Foretravel Owner's Manual (wiring diagram) have any clues?  I found a HWH page that lists many owner's manuals.  Scroll down the page until you reach "Slide-Out Systems (with HWH Leveling System)".  You might find a manual that covers your system, and hopefully shows the power supply for the aux pump.

http://www.hwhcorp.com/ml54800_srvc.pdf

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #2 –
Our 2004 works like you stated. When working on the 12 volt air compressor, such as filling the desiccant filter, it is necessary to pull the inline fuse and turn off the air leveling system. Every thirty minutes when using the air leveling system, the system turns on and checks for level. If not level. the system will call for air and the 12 volt compressor will turn on. The 12 volt compressor will turn on even if the fuse is pulled.
Larry

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #3 –
Put your on/off switch in the red wire going into the compressor motor.  The motor will not run without power no matter once!hat system is telling it to run.  I added a switch in the driver's area.  You can use a relay and much smaller wire to control the relay if you want.

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #4 –
Quote from: Roger & Susan in Home2 –
Put your on/off switch in the red wire going into the compressor motor.  The motor will not run without power no matter once!hat system is telling it to run.  I added a switch in the driver's area.  You can use a relay and much smaller wire to control the relay if you want.

Roger, as I'm sure you know, the compressor motor is controlled by a relay that actuates when the pressure drops below approximately 70 psi. With the on-off switch in the hot lead to the motor, the relay will still engage when the system calls for the motor to run. The motor won't run but the relay stays activated and gets very hot.

After discovering that, I put my on-off switch in the wire from the pressure switch to the relay coil. That prevents the relay from engaging and the compressor motor doesn't run.

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #5 –
 Rich wrote...
"I also found something else that I did not expect.  Several years ago, I installed a switch in the 12V compressor power line so I could turn it off to refill the desiccant without having to pull the fuse.  This switch will turn the compressor on/off when the slideroom bladder is being filled or deflated.  I found that the compressor also gets power from another source.  With the switch off, the compressor will still come on when the leveling system is calling for air.  I'd be interested in any comments on this little discovery."

There is a jumper wire in the pressure switch that bypasses the pressure switch and starts the compressor when the leveling system is used , even when manually leveling.

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #6 –
Ed and Roger,

So it seems like it would take two switches to completely and safely turn off the compressor. 

As it is right now, I need to turn off the switch I installed and the leveling system if I want to make sure the compressor will not run while I'm changing the desiccant.  And anyone who does not have a switch and pulls the fuse to do this should also turn off the leveling system.

Rich

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #7 –
I almost never leave the auto level and the compressor on. My coach will stay where I put it for days with maybe one small adjustment. Air system on the 2001 is different from the 2002 and later.

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #8 –
I realize that this is old but....the regulator on my slide manifold leaks around the threaded portion. I shut off the bladder valve at the top of the manifold, but the reg continues to vent till the 12v compressor comes on and works a long time to catchup. Is the regulator repairable, or replaceable?

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #9 –
Cheeper in the long run to just replace it, also the unloader valve (aka "pop off valve")

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #10 –
Quote from: toyman –
I realize that this is old but....the regulator on my slide manifold leaks around the threaded portion. I shut off the bladder valve at the top of the manifold, but the reg continues to vent till the 12v compressor comes on and works a long time to catchup. Is the regulator repairable, or replaceable?


I may have the piece you need in my spares. Picture of the exact item?  Also, depending on which item, the o rings from the six pack rebuild fit fine.

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #11 –
Dan, I'll try adding the picture, but it's the round black thing on the manifold with the threaded shaft in the center. I finally got where I could see what it's doing, it's got a small bleed hole on it and it's venting thru it all the time. This photo is not mine, I have only one slide. Wonder if FT or MOT would have a replacement....what do I ask for ?

Where are you located ?

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #12 –
Quote from: toyman –
Wonder if FT or MOT would have a replacement....what do I ask for ?


Dave - likely you can e-mail them a photo of what you need.  Or some folks at both places have signons here - you could ask them to look at your post and photo.

Re: HWH Slideroom Bladder Manifold repair/rework

Reply #13 –
Quote from: toyman –
Dan, I'll try adding the picture, but it's the round black thing on the manifold with the threaded shaft in the center. I finally got where I could see what it's doing, it's got a small bleed hole on it and it's venting thru it all the time. This photo is not mine, I have only one slide. Wonder if FT or MOT would have a replacement....what do I ask for ?

Where are you located ?



Dave,

I am currently in Spokane WA.  1st try disassembling your air reg carefully noting how it goes back together. Probably just a piece of debris in there.

If not, I will send you my spare for free if you re-imburse my mailing and packaging costs.  I'll have it packaged up and sent if you need it.

Edit - two small thru bolts hold the air reg in place. Bolts are on the back of the mounting block.

You may remember me from Livingston a few years ago, you showed me your FT and you checked out my Bluebird BMC.