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Topic: External Compressor Connection to Add Air to Wet Tank and Service Tanks (Read 1573 times) previous topic - next topic

External Compressor Connection to Add Air to Wet Tank and Service Tanks

Put this over here for reference.

This is something I have wanted to do for a long time.  Model years later then 2001 have a larger aux compressor and and a means to add air to the wet tank.  They use a desiccant container to dry the air.  I have alway thought I could add air before the coach's air dryer which (with the ignition on to power the air dryer heater when the outside temp is cold) would dry the air, add it to the wet tank and then to the front and rear service tanks,  Charge up the air without running the engine.  Pretty helpful when you are chasing air leaks.

So I removed the compressor air line from the air dryer and removed the fitting.  I replaced it with a 1/2" 90° street ell, a 1/2" x 2" nipple and a 1/2" Tee,  On the side of the Tee I reinstalled the compressor air line fitting and reattached the compressor air line. On the other end of the Tee I added a 1/2" 45° street ell, a 1/2" to 1/4" bushing, a 1/4" ball valve and a short air hose to a female air fitting. 

A male fitting would work here but I thought it would be easier to keep the dirt out of the female fitting.  I have a male to male adapter to connect to the aux air fitting in the LP compartment.  The short hose lets the female fitting get tucked into the end of a frame tube out of harms (and dirts) way.

Works great! 

Thanks to Old phart phred for a bit of inspiration and Craneman for some technical detail.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: External Compressor Connection to Add Air to Wet Tank and Service Tanks

Reply #1 –
Nice work Roger I like the idea of this set up, thinking on adding this to my coach.  I have an external isolation valve, should the T be added on the dryer side of the isolation valve? My thought is if the isolation valve works in conjunction with the governor/compressor the valve should be bypassed to add external air.  Thoughts from those that understand the workings of the isolation valve..

Bill and Marsha Kuykendall
1999 Foretravel U320 36' CAI
Build Number 5446
2006 Lexus GX 470

Re: External Compressor Connection to Add Air to Wet Tank and Service Tanks

Reply #2 –
The tee can be before the isolation valve. The line from the D-2 unloader port would only close the valve after the compressor cycled and the tank was full.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: External Compressor Connection to Add Air to Wet Tank and Service Tanks

Reply #3 –
Quote from: craneman –
The tee can be before the isolation valve. The line from the D-2 unloader port would only close the valve after the compressor cycled and the tank was full.
Thanks Craneman, that's what I needed to know.
Bill and Marsha Kuykendall
1999 Foretravel U320 36' CAI
Build Number 5446
2006 Lexus GX 470

Re: External Compressor Connection to Add Air to Wet Tank and Service Tanks

Reply #4 –
Another Roger project checked off of my list. 

I was stuck removing the existing air line until I was at my brother-in-law's shop.  He had the necessary wrenches (1 1/16 & 1 1/8 open end wrenches as I recall) that are 2 feet long.  No problem getting the air line off.

Worked just as Roger described.
Tom and Lisa

2003 U320 38' PBBS
Build No. 6217