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Topic: "air tanks" switch  (Read 385 times) previous topic - next topic

"air tanks" switch

Hello, On my '02 36' U320 with slide outs there is a toggle switch on the drivers left hand console (below the transmission gear selector)
labeled "air tanks".  I've been sorting out and trying to learn the systems on board ( new to me about two months now).  I am unable
to identify it's  purpose and use? I'm grateful for any insights offered.
 
2002 U320 36'

Re: "air tanks" switch

Reply #1 –
It opens a solenoid valve that allows the HWH aux compressor to air up the main air tanks.  It should be kept closed in general.  It was added sometime in 2002 so folks could air up their coach before departing a campground without starting the coach engine (courtesy towards neighbors).

The aux compressor (especially its mini dryer) isn't designed to be used for this purpose on a regular basis.

BTW, that solenoid valve has been known to leak through.  If you ever see the pressures in your A and B tanks increasing with the aux compressor running but that switch and the main coach engine off, it's likely that valve.
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: "air tanks" switch

Reply #2 –
thank you , simple enough. There has been a toggle switch added also to cut power so the pump won't cycle, at night lets say. At times of storage is there a problem leaving the aux. air pump off line allowing the air bladder seals in the slides to lose pressure? Not that note a leak just assuming over a period of weeks they would occur. 
2002 U320 36'

Re: "air tanks" switch

Reply #3 –
Quote from: Bill Petersen –
thank you , simple enough. There has been a toggle switch added also to cut power so the pump won't cycle, at night lets say. At times of storage is there a problem leaving the aux. air pump off line allowing the air bladder seals in the slides to lose pressure?

If it's sheltered storage (so no risk of rain hitting the coach) and level (so you can shut the leveling system off), there should be no problem leaving the aux compressor off. 

If you do that, consider dumping the coach air so it can't settle unevenly (six-pack solenoid or other leak) and twist the frame (potentially damage the windshield).

We used to do this and pull the inline fuse for the aux compressor (we didn't have an added switch).  Our concern was more the unloader solenoid (a NO one) failing to seal and causing the compressor to run continuously.  That solenoid (aka the "pop-off") can be a problem-child due to debris that can contaminate the seat.
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: "air tanks" switch

Reply #4 –
thanks for passing on this useful information, I'm still in state of not knowing what I don't even know!
all the best to you! Bill
2002 U320 36'

Re: "air tanks" switch

Reply #5 –
I put a fused inline switch on my compressor and dropped the coach in storage in my garage and threw the switch. It was just a mins work to throw it again when unplugging and getting ready to go
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: "air tanks" switch

Reply #6 –
Quote from: Bill Petersen –
thank you , simple enough. There has been a toggle switch added also to cut power so the pump won't cycle, at night lets say. At times of storage is there a problem leaving the aux. air pump off line allowing the air bladder seals in the slides to lose pressure? Not that note a leak just assuming over a period of weeks they would occur. 
This was also done on my coach prior. It was the power wire going to the electric motor. Initially it sounded like a sound resolution, BUT the system is still functioning and the control relay you thought you defeated is still closing and it itself is now drawing power and is a potential fire hazard being energized for long periods time. Gets real hot. Better to deactivate the control solenoid shutting all of it down instead of only half. IE no need for a switch to shut the motor off. Shut the solenoid off preventing the motor to run.
In regards to the slide being left deflated, the original will eventually relax and allow dust , bugs, water to enter. The new bladders when relaxed still stay in contact well.

Re: "air tanks" switch

Reply #7 –
Scott, how did you cut power to the solenoid? seems to me installing a rated in line switch on that no.8 gauge wire prior to the solenoid is straight forward. I see its supplied/protected by a 15a breaker. 
2002 U320 36'