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Topic: No power to A/C dash Compressor (Read 437 times) previous topic - next topic

No power to A/C dash Compressor

Previous A/C compressor clutch was engaging but determined it needed replacement. After installing new A/C compressor and pulling vacuum and charging it was discovered that in the mean time power to the compressor had failed. Was able to manipulate the new charged  compressor into engaging with a jump box, so determined with a test grounding light that the supply plug power has failed? Thinking there is a fuse somewhere that has blown? Any information about dash air fuse location? I looked at Foretravel owners manual wiring diagram but am overwhelmed! Any information to locate power failure is appreciated.
Phillip M.
2000 U320 40'

Re: No power to A/C dash Compressor

Reply #1 –
I have the same year coach as you do. There is a relay under the bed that is for the ac compressor. A 15 Amp relay that is with the three cluster of relays on the panel in front of the engine compartment. My contacts were really corroded so I took everything apart and clean well the replaced relays all three of them just to be sure no more problems.  There are more relays in front of the passenger seat behind the removable panel. There are some there for the ac blower and heater so might check those also. They are listed on your schematic for the coach wiring. That fixed mine. Hope this helps.
Larry
Larry & Debbie Town
2000 U320 4210 
Previous 88 GV

Re: No power to A/C dash Compressor

Reply #2 –
Our compressor and condenser fan each have their own simple 12v relay and breaker mounted to the isolator panel steel plate.

Our refrigerant lines each have series wired low and high pressure switches, that both have to be closed to flow power to compressor clutch coil.

Re: No power to A/C dash Compressor

Reply #3 –
Just to put a picture to what Larry and Barry posted, here is what is on my coach.  Forward bulkhead of the engine compartment, accessed under the bed. 

Richard
Jan & Richard Witt
1999 U-320  36ft WTFE
Build Number: 5478 Motorcade: 16599
2011 Jeep Wrangler Unlimited w/Air Force One
Jan: NO5U, Richard:KA5RIW
The selected media item is not currently available.

Re: No power to A/C dash Compressor

Reply #4 –
Thanks everyone for the valuable input, spot on! Diagnosed my problem to be the relay circuit on the firewall under the bed as recommended. Now I just have to locate replacement part and install. This forum is invaluable for diagnostic issues on our coaches!  Appreciate each one of you!
Phillip M.
2000 U320 40'

Re: No power to A/C dash Compressor

Reply #5 –

If yours turns out to be like mine was, it's the circuit breaker.  The A/C compressor clutch was one size and the condenser fan is the other size...I don't remember which was 15a and which was 20a, but I got them here:

Amazon.com: Short Stop Circuit Breaker 15A Plastic and Brkt Type-1 12V :...

Amazon.com: Short Stop Circuit Breaker 20A Plastic RT and Brkt Type-1 12V :...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Keith
2003 U320 38' #6197

Re: No power to A/C dash Compressor

Reply #6 –
Quote from: New24Travel –
Diagnosed my problem to be the relay circuit

If it is a failed relay then look for an RL-40 relay. They now make a new upgraded water proof version but you will need to change out the plug.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: No power to A/C dash Compressor

Reply #7 –
Roger Burke spent lots of cash to try and get the dash A/C to work. 95% of my coaches the dash air was inop. I just run the generator and the 3 roof airs.

Re: No power to A/C dash Compressor

Reply #8 –
Issue resolved, replaced 15 amp 12v circuit breaker on firewall beneath the bed, up and running cooling well. Heading out next week fingers crossed :). Thanks to all.
Phillip M.
2000 U320 40'