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Author Topic: Dometic AC Thermostat  (Read 236 times)


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Dometic AC Thermostat
« on: September 20, 2017, 07:08:20 PM »
I have a 2004 Travel Supreme. We have two ac units. One in the bedroom and one in the main living area. The one in the main living area sometimes works awesome and other times it doesn’t. Yesterday, the thermostat wouldn’t turn on. Ive checked all the fuses and breakers. Does this just mean I need a new thermostat? I have thermostat part number 3109228. It’s a digital Duo therm.



Gary RV_Wizard

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Re: Dometic AC Thermostat
« Reply #1 on: September 21, 2017, 10:51:55 AM »
Maybe. The thermostat needs 12v power, so check the wiring behind it to make sure it has a reliable source.  When you sya the t-stat won't turn on, do you mean it doesn't light up, or merely that it doesn't turn the a/c or furnace on? Two different problems...

That part number of the Comfort Control Thermostat, a fairly sophisticated beast and also know to be troublesome after awhile. You may have either the 4-button or the 5-button model. Here's a trouble-shooting document:

And Op manual: http://assets.interactcp.com/fretzrv/pdfs/Duo_Therm_Comfort_Control_Manual.pdf

If you have the older 4-button type, it is obsolete and an upgrade kit is required for replacement [if that ends up being necessary].
« Last Edit: September 21, 2017, 10:57:42 AM by Gary RV_Wizard »
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