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Jones1's avatar
Jones1
Explorer
Aug 30, 2019

Evans?Tempcon a/c & air dump valve '99 DS, Frt Liner

Little help if possible. I have a '99Dutch Star,Frt Liner,Cat3126.
I have a problem with the Evans Tempcon unit in that the vacuum pump clcles on and off.It does operate the units doors. It started the pump would run continuously. Carried it to RV service center and he replaced the vac. lines from pump to vac. tank and from tank to the selector switch on the dash. Pump quit running cont. but cycles on and off. I pulled the line from pump,plugged ,pump shut off,pulled the small line from the resv,plugged theoutlet on the tank,pump shut off,pinched the line from the res.at the dash selector switch and the pump cycles on/off. All lines are new to this point.

Also having a problem with the dump valves for the air bags. Found the fuse in the HWH control unit(HWH 310) system. Replaced the fuse and as soon as I try to dump the bags blows fuse. It lookslike the system has 3 dump valves. What would be the procedure to check these valves, if I can located them? I assume Newmar installed the levelin system not Frt Liner.
Any advice help would be most appreciated.
Thanks for reading
Roy Jones
Class A
  • Jones1's avatar
    Jones1
    Explorer
    Aug 31, 2019
    Doug
    Thank you very much for the response/information. I know the vac. pump has always cycled but I just didn't remember it being that often.

    Regarding the dump air system, I assume Newmar installed the complete level system including the dump valves. I guess the valves will be in the air line feeding the air bags (two in the rear and one in the front. This is a 310 leveling system.
    It would be nice to have a good RV service center in the Birmingham, Al.area.
    Again Thank You
    Roy Jones
  • dougrainer's avatar
    dougrainer
    Nomad
    Aug 30, 2019
    EvansTempcon systems have inherent vacumm leaks. Always have. The Vacumm motors are not air tight. So, the 12 volt pump will cycle. NOTHING can be done to fix this.
    The AIR bag system is Frtliner installed and the HWH system taps into the Air bag system. So, you can have a problem with Frtliner or HWH. Frtliner does NOT work on HWH systems. HWH jacks are installed by Newmar and the Harness and solenoids are HWH parts as is the wire harness to the solenoids. If the fuse blows, odds are you have a shorted solenoid, but a long shot would be a short in one of the 3 dump valve wires in the HWH harness. This is a link for your year model HWH service manual. You will have a 300 or 600 series HWH system IF NOT computerized(Auto) leveling, this is a good Service manual. Doug

    https://www.hwhcorp.com/ml13514.pdf

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