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bodacious's avatar
bodacious
Explorer
Jan 11, 2014

Need help with Dometic duotherm

I can't get air conditioner or furnace to work. Tried new batteries in the remote. Neither works with manual override either. Seems like it may be missing some control voltage because the "on" light in the reciever does not light (remote or manual). I've checked all fuses and circuit breakers. The reciver (in ceiling) has a phone type jack going to it but don't know where it terminates. System is in a 2005 Cougar 309EFS 5er.
Any ideas on where to look for problem?

2 Replies

  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Jan 13, 2014
    The phone cable in ceiling gos to the comfort control center (t-stat)

    There is also a 3A fuse on module (in ceiling). check that it isn't blown

    Try a system reset.
    On the t-stat turn the ON/OFF switch to OFF
    Simultaneously Depress and hold the MODE and ZONE push-buttons while turning the ON/OFF switch to "ON". 'FF' should appear in the LCD display until the MODE and ZONE push-buttons are released.
  • AVTravler's avatar
    AVTravler
    Explorer
    Jan 13, 2014
    Did you check both the 12v and the 120v fuses/breakers. Sometimes a fuse looks ok, but I'd recommend putting in a new fuse, just a thought as I had a similar problem. Good luck.

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