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Topic: Dash air question? (Read 537 times) previous topic - next topic

Dash air question?

The coach is in the shop for A/C troubles.
Tech said the unit is empty of Freon, but yet the system held vacuum all night.
Can anyone speculate as to why this can be.
Thanks in advanced.
'02 U295 36'
Build #5937

 SKP#104358
Motorcade#17428

Re: Dash air question?

Reply #1 –
Quote from: Tom Endres –
The coach is in the shop for A/C troubles.
Tech said the unit is empty of Freon, but yet the system held vacuum all night.
Can anyone speculate as to why this can be.
Thanks in advanced.
Maybe the vacuum compresses whichever seal or component is leaking, while the pressure of the freon creates a leak?  I would think they need to do a dye test to figure it out.

Re: Dash air question?

Reply #2 –
I have chased that situation before, and as stated above the vacuum will suck an o ring or seal and hold vacuum. Then when pressurized the system leaks. Dye or gas sniffer is what I use to find them.
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: Dash air question?

Reply #3 –
my Freon leak turned out to be a loose cap for the hi pressure charging port.  I must have left it loose after adding Freon.
Rick & Deborah Webster
2002 3610 U320 #5964
2014 Jeep Wrangler Sahara JKU- 'Copperhead'
Richland Chambers Lake, East Texas

Re: Dash air question?

Reply #4 –
The charging port cap is more of a dust cover than a cap.  Your leak may have been an intermittent issue with the schraeder valve under the cap.  When the schraeder valve is working correctly, the system should hold pressure without the cap.  I'd keep an eye on it and maybe replace that valve.

Re: Dash air question?

Reply #5 –
Quote from: bdale –
The charging port cap is more of a dust cover than a cap.  Your leak may have been an intermittent issue with the schraeder valve under the cap.  When the schraeder valve is working correctly, the system should hold pressure without the cap.  I'd keep an eye on it and maybe replace that valve.
I have bought the 2 tools one for R-12 and two for R-134 that change the valve core without losing the freon.

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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