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Dash ac

Thanks to  you all members , my FT problems are getting fixed one after the other
Today i tried the dash AC
When i didn't feel cold blow, i went back by the engine and noticed that the AC compressor clutch is not engaged
Unplugged the inline fuse , it was good
Tested the wire , there was no power
Any idea where i should search ?
Edmond
1998 U295
Edmond
1998 Foretravel U295
Turlock Ca

Re: Dash ac

Reply #1
On your coach there is a relay that is on the isolator board that controls the clutch and a second relay that controls the condenser fan along with a self resetting breaker for each.  Due to location and age any one of these can be bad so check them out. You might just find that you will have to rebuild the isolator board as others have done. Some of the boards were mounted behind the left rear tire and some on the firewall under the bed.

You need to hunt around in the Wiki section and find a B-2126 print for your 12VDC system as it is a must for a DIY person.

Mike
Pamela & Mike 97 U 320

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

Re: Dash ac

Reply #2
In addition to what Mike points out, there is a pressure switch located very near the condenser unit.  On my coach the wire that plugs into that switch had come loose, a very simple fix.  The condenser is the radiator like unit located on the driver side behind the rear wheels near the muffler. 
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
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Re: Dash ac

Reply #3
More than likely it's low on freon. You can start with a set of a/c gauges for 134 freon and bypass the low pressure switch. Look for any trace of leaks closely oil/dirt on any lines, compressor shaft seal etc. There are a few components to diagnose. Or you can throw parts at it. I would suggest some help from someone with knowledge about a/c systems. Jim.   
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc

Re: Dash ac

Reply #4
thank you all , I will check the freon leak first if any , i will look behind driver side front wheel , is AC condenser there? do you mean by generator muffler?
sorry I am new, and even don't know how isolator in my FT looks like any pictures to show the isolator and the relay and the condenser will greatly appreciated
Edmond
1998 U295
Edmond
1998 Foretravel U295
Turlock Ca

Re: Dash ac

Reply #5
1, i will look behind driver side front wheel ,
2. is AC condenser there?
3. do you mean by generator muffler?

1. No look inside the door behind the drivers side rear tires
2. same area behind the drivers side wheels. That is what is behind the little grill you see on the side wall
3. No refer to # 1.

Mike


Pamela & Mike 97 U 320

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

Re: Dash ac

Reply #6
There could be a leak anywhere in the system, mine was one of the o rings for the receiver/dryer at the condenser located where Mike stated behind the driver rear wheel in the louvered door. Jim.
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc

Re: Dash ac

Reply #7
Edmond, Where are you located? Sounds like you could use some help on this one. Could be simple or not, really need some experience to help you hands on. Jim.

 P.S. your a/c system has no Isolator.
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc

Re: Dash ac

Reply #8
Jim i am in central california, don't know any one with a 1997 or 98 foretravel
If i find one i don't mind to drive there and ask questions i need if the owner is willing to help
I am sure ever body purchased his/her first RV at some point and had same need as i do
Believe it or not , i asked a local RV shop to go there and have them show me show me how Rv components work, roof ac, Ref, stove, ice maker, water heater etc.
They asked 864.00 to do so
Edmond
1998 U295
Edmond
1998 Foretravel U295
Turlock Ca

Re: Dash ac

Reply #9
Edmond, 1998 U320 in Tucson.  I would love to help you understand the systems.  Will be about two weeks until I am available.  Send a PM.
Matt B
1998 u-320

Re: Dash ac

Reply #10
Jim i am in central california, don't know any one with a 1997 or 98 foretravel
If i find one i don't mind to drive there and ask questions i need if the owner is willing to help
I am sure ever body purchased his/her first RV at some point and had same need as i do
Believe it or not , i asked a local RV shop to go there and have them show me show me how Rv components work, roof ac, Ref, stove, ice maker, water heater etc.
They asked 864.00 to do so
Edmond
1998 U295
Edmond
1998 Foretravel U295
Turlock Ca

Re: Dash ac

Reply #11
...don't know any one with a 1997 or 98 foretravel...
If i find one i don't mind to drive there and ask questions i need if the owner is willing to help
We have quite a few members in California.  See map link below.  Zoom in on the map to your location.  Pick a member marker nearby and click on it.  In the pop-up box click on the member's name to open their profile page.  Check their coach model info to see if it is close to your model year.  Check how long they have been Forum members.  If they provide a contact link, you could try sending them a PM or email.  I don't think any of our more experienced members would mind chatting with you to answer some questions, or even possibly meeting up with you.  Worst case scenario they might say "Sorry I can't help (for whatever reason)".

https://www.foreforums.com/index.php?action=GoogleMap
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
"Nature abhors a vacuum"

Re: Dash ac

Reply #12
It's most likely low on refrigerant charge. Even when everything is good and new, the refrigerant will slowly leak out through rubber hoses, compressor seal etc. When the RV is 25 years old, it will leak out even faster and may require topping off every once in a while.

Compressor leaks around the shaft seal come with age. If you can't find the leak anywhere else, it could be hidden behind the compressor clutch.
1998 U270 34'

Re: Dash ac

Reply #13
Edmond, as far as your dash a/c system it's basically the same as any vehicle system. Any auto repair tech that knows a/c can diagnose the system. He will first connect a set of gauges and go from there. Finding one that is willing and has the space may be a bit of a search but in your area, Turlock should be no problem. If you were close to me I wouldn't mine helping you but I'm about 6 hours from you. I just hate to see you throw parts at the a/c system. The suggestion to find someone from the forum near you is a great idea for getting to know your coach, all these people are great. Plan on meeting with us in Quartzite next January, allot of good knowledge shows up there.  Jim. 
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc

Re: Dash ac

Reply #14
thank you all , I will check the freon leak first if any , i will look behind driver side rear wheel for the AC condenser .
sorry I am new, and even don't know how isolator in my FT looks like any pictures to show the isolator and the relay and the condenser will greatly appreciated
Edmond
1998 U295
Edmond
1998 Foretravel U295
Turlock Ca

Re: Dash ac

Reply #15
.... don't know how isolator in my FT looks like any pictures to show the isolator...
Edmond
1998 U295

Edmond, if you are asking about the battery isolator, it will not be in any way directly related to your dash A/C issue other than perhaps location with A/C relays.

The battery isolator takes input from the alternator and then charges the chassis and house batteries and doesn't let them discharge as one.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Dash ac

Reply #16
The reason the isolator board was brought up was to help him find the breakers and relays that control the compressor clutch and the condenser fan.  These items will be mounted on that board along with the boost relay and aux start relay.  Somehow we got off track as to the isolator in relation to the A/C system.

Mike
Pamela & Mike 97 U 320

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

Re: Dash ac

Reply #17
Buy a guage set with adapters and check pressure at rest.  Any port that you can reach will work.  Testing pressure should be something over 100#.  If you have a leak.  It will be near zero. 
Some pressure indicates a small possibility of the system working.
 The ports may be near the compressor and or near the condenser.    Don't fret over high or low at this point .
 The compressor clutch power passes through a few controls. First the power up relay , then the pressure switches.  Last the clutch magnet itself . Look on u tube for how to check and adjust the clutch air gap. If the power gets that far.
The power up relay may be grounded by the pressure switches. A schematic will show details regarding current path.
Of course you can check the compressor and clutch by hot wiring directly to it. It should clunk if not running and clunk/ spin if running.

Re: Dash ac

Reply #18
Our 99, 36' coach dash AC charge is 5lbs
David & Emma Roche
Dino (Golden Doodle)
1999 U270 WTFE 36' Build # 5534
Xtreme "Lights, Stripes & Roof"
Motorcade# 18321
Dayton, Ohio
Towd: Jeep Grand Cherokee
Two Townie Electra Bikes

Life is made to enjoy, the Foretravel helps!