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Topic: Aux compressor check valve (Read 502 times) previous topic - next topic

Aux compressor check valve

I have the non-stop compressor running issue and at first check I see that the desiccant and water separator need replacement so I ordered them but the manual shows a check valve between the two units that my setup doesn't have. It's a straight through male to male brass fitting. Should I add one? FT has them and said if I look at the one in my setup I'd see that it was a check valve it it certainly isn't. Michele's pictures look a lot like mine.
I'm not sure this relates to the pump running issue but want to fix it first and then see what the situation is.
What do you think?
Thanks,
Tyson
2006 Nimbus 334
15467
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Aux compressor check valve

Reply #1 –
When the compressor is running, is air coming out the bottom of the solenoid condensate bowl (the one without the desiccant)? 

That is a NO (normally open) solenoid valve that should be open ONLY when the pump isn't running (to expel condensate - it's the "whoosh" you hear when the compressor shuts off).  It should CLOSE when the pump is running to allow pressure to build.

If air is coming out with the aux compressor running, most likely you have a bad solenoid valve.  It's a fairly common issue.

If no air is coming out of the bottom of that solenoid valve but the compressor won't shut off, there is likely an air leak somewhere.

Odd that you would be missing a check valve, but being a 2006 Nimbus anything was possible with those builds.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

Lifetime Escapees' member SKP 82766
Former 1999 30IB Lazy Daze (2000-2004)
Former 2003 U320 (2004-2016)
Former 2017 LTV Unity (2017-2023)
Shopping for our next coach

Re: Aux compressor check valve

Reply #2 –
Quote from: flyin-tyson –
...the manual shows a check valve between the two units that my setup doesn't have. It's a straight through male to male brass fitting. Should I add one?
Have you actually removed the "straight through brass fitting" and verified that it is not a check valve.  They could appear very similar externally.

I don't know what "Michele's pictures" you are referring to.  Where are they located?

Can you post the page from the "manual" showing the diagram of your aux air compressor?  Over the years, HWH has supplied several different compressors, and each variation is plumbed differently.

I am providing a link below to a .pdf diagram of the aux compressor on a 600 Series leveling system.  Your compressor may be different.

On my diagram, if the check valve (4) was replaced by a straight male/male nipple, it would result in air flowing backwards from the suspension to the compressor.  This might cause non-stop compressor running - I'm not sure.  I'd need to experiment to find out.


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
"It goes without saying..."

Re: Aux compressor check valve

Reply #3 –
I don't know how to add a picture, the button asks for a url?

I have all the parts on the bench and the junction isn't a check valve, just a straight m/m.

Of course it's a 2006 and has worked this way for years and at least since I bought it last year.
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Aux compressor check valve

Reply #4 –
I felt no leak when it was running but the water separator had an inch of water in it so the valve wasn't working and the desiccant filter was pink and the metal containment cover was rusted so I have all on order.
I'll be adding a pressure gage so I can see what's happening.
Tyson
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Aux compressor check valve

Reply #5 –
It could be just the relay contacts are stuck so I'll check that too....
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Aux compressor check valve

Reply #6 –
Quote from: flyin-tyson –
Of course it's a 2006 and has worked this way for years and at least since I bought it last year.
In that case, the hardware configuration is probably correct, and I wouldn't worry about the nipple.  As I said, HWH changes how they plumb the compressors on different models.

You may have a leak someplace that is not allowing the compressor to reach cut-out pressure and shut off.  Put it back together just like you found it (except for the new parts) and see what happens.  If it still won't shut off, spray soap solution all over the lines and fittings and look for leaks.

Another possibility is a failed normally closed pressure switch (number 1 on my diagram).  On your setup this would equate to whatever device turns the compressor on and off.
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
"It goes without saying..."

Re: Aux compressor check valve

Reply #7 –
Quote from: flyin-tyson –
I don't know how to add a picture, the button asks for a url?


Quick and dirty is to have the folder their in on your computer open, then drag n' drop them into the post. 

Slightly more involved is being sure you're in "full editor" mode, scroll below the post text box to where it says "Attachments and other options", click "Selecting them" and then select the files from your computer.

One last method is to create a folder, upload the photos to the folder, then grab the code that says "SMG ID" and plop it in your post.  That's particularly useful when you want to create a tutorial post or have some technical documentation you want to upload to the forum.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

Lifetime Escapees' member SKP 82766
Former 1999 30IB Lazy Daze (2000-2004)
Former 2003 U320 (2004-2016)
Former 2017 LTV Unity (2017-2023)
Shopping for our next coach

Re: Aux compressor check valve

Reply #8 –
Quote from: Chuck & Jeannie –
I am providing a link below to a .pdf diagram of the aux compressor on a 600 Series leveling system.  Your compressor may be different.

A 2006 should have a 2000 series, I think.  The slide bladder system adds complexity and the newer  series use the TA-4101-DC aux compressor.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

Lifetime Escapees' member SKP 82766
Former 1999 30IB Lazy Daze (2000-2004)
Former 2003 U320 (2004-2016)
Former 2017 LTV Unity (2017-2023)
Shopping for our next coach

Re: Aux compressor check valve

Reply #10 –
Yes I have three slides with bladders.

I did order the check valve from FT so I can put it back together as it was and also try the check valve for an option.

Tyson
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Aux compressor check valve

Reply #11 –
So the good news is after replacing water separator and related solenoid, the desiccant filter, and adding a pressure gauge it appears all is well! It pressurized right up to ~115psi and cut off and hasn't turned back on. It gave a nice puff when it shut down so I think we are back fully functional and better than it was before based on the water that was sitting in the water trap bowl.
I did receive the check valve from FT with the other parts I ordered but didn't open it, not sure if it would be used elsewhere so I should hold on to it or return for refund minus 20%.....
Thanks for your thoughts...
Tyson

PS still waiting for the call back from HWH technical support from my call two days ago to ask about the check valve....
Tyson
2004 295 3610 WTFS
2010 Honda CR-V
Motorcade #18344
AA1DS

Re: Aux compressor check valve

Reply #12 –
Keep it.  You should have a special drawer or container for "Spare Parts".  If you don't, start one now.  You will tend to accumulate parts as you go along, and it's nice to have them all in one place for handy quick access.
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
"It goes without saying..."