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dsikes8's avatar
dsikes8
Explorer
Mar 20, 2017

Duo-therm model 57915.541 ducted unit not cooling

We purchased our travel trailer back in October from a less than honest couple. We have done some work on the interior and this weekend was our first chance to take it out. It got a little warm in the camper and I wanted to cool it down. The AC would not work. When I turned it on with the fan speed set to Auto it would do nothing. If I changed the fan speed to low it would blow but not cool. What is the next step? Can these units be serviced? The trailer is an '08. Should I replace the unit?

10 Replies

  • dougrainer's avatar
    dougrainer
    Nomad
    Apr 08, 2017
    dsikes8 wrote:
    I ended up purchasing the Dometic B59516.XX1C0 Brisk II polar unit. Should my Duo Therm Comfort Control Thermostat work with this unit?

    Thanks in advance for the help.


    Yes, the upper units (except the 600 series Penguin) are all the same for the power hook up. Doug
  • dsikes8's avatar
    dsikes8
    Explorer
    Apr 08, 2017
    I ended up purchasing the Dometic B59516.XX1C0 Brisk II polar unit. Should my Duo Therm Comfort Control Thermostat work with this unit?

    Thanks in advance for the help.
  • dougrainer's avatar
    dougrainer
    Nomad
    Mar 24, 2017
    Fulltimer50 wrote:
    Thats the best way. If you replace everything you have a better chance of fixing the problem. Money no object makes it easier, too.


    ALL he has left is the upper control box:B Doug
  • Fulltimer50's avatar
    Fulltimer50
    Explorer
    Mar 24, 2017
    Thats the best way. If you replace everything you have a better chance of fixing the problem. Money no object makes it easier, too.
  • dsikes8's avatar
    dsikes8
    Explorer
    Mar 24, 2017
    Thanks for the model number Doug. I ordered a new upper unit and thermostat tonight. I will let you know how this goes. I appreciate all the help.
  • dougrainer's avatar
    dougrainer
    Nomad
    Mar 20, 2017
    dsikes8 wrote:
    We waited about 15 minutes. When the fan did run the compressor never kicked in. I am thinking it is best to replace the unit. I am fairly handy and would like to tackle this myself. Would there be a benefit of upgrading to a 15,000 btu system? Which model would you all recommend. Thanks for the advice so far.


    You may have 2 problems. Or just 1 problem. The top unit is just that, The top unit. The control box and the wall tstat are separate parts. So, if you have a Tstat/control board problem, a new upper unit will not fix anything. YES, upgrading to the 15k is a good move for what extra dollars they cost. B59146.XX1J0 is the 15k model of your unit. Ducted or non ducted makes no difference on the upper unit. Doug
  • dsikes8's avatar
    dsikes8
    Explorer
    Mar 20, 2017
    We waited about 15 minutes. When the fan did run the compressor never kicked in. I am thinking it is best to replace the unit. I am fairly handy and would like to tackle this myself. Would there be a benefit of upgrading to a 15,000 btu system? Which model would you all recommend. Thanks for the advice so far.
  • dougrainer's avatar
    dougrainer
    Nomad
    Mar 20, 2017
    Chris Bryant wrote:
    Because it won't come on at all in auto mode, I suspect the thermostat.


    They probably did not wait long enough, for the Fan to come on. Doug
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Mar 20, 2017
    With it in auto....no fan and no compressor (but fan does work)

    Could be as simple as start/run capacitors, thermostat or bad compressor motor

    Units can be 'serviced' as in fan motor, capacitors, replace thermostat etc BUT w/o adding service valves units are sealed on coolant side.

    If not handy, understand DC & AC electricity and know how to use a voltmeter it would be best to have mobile rv repair check unit out......


    If handy these should help
    Installation manual for 579 series

    Duo-Therm Service Manual...pg. 104 troubleshooting for roof top A/C Units

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