# DuoTherm Thermostat replacement problem



## RonWSl

I have a 95 HR Endeavor with dual AC roof units. Each is controlled by a separate thermostat. The Rear AC stopped working, and it has been determined that the Thermostat is bad. One would think this is a simple problem - buy a replacement stat and install it - WRONG. The thermostat is a DuoTHerm, Model #3105356.004. A web search failed to find one. I stopped at several RV dealers, no luck. Last RV dealer called Diometic and learned that my thermostat had been replaced by Model #3108701.339. Problem solved you say - WRONG again. That unit has now been replaced by Model #3307713.010, which not only requires the purchase of the thermostat, but a control unit for the AC itself and some wiring, etc etc, all at a cost of almost $350. I would like to wire in another stat, have seen several articles on replacement of the analogs with the Hunter digital battery operated units, BUT, my unit doesnâ€™t have separate colored wires, but a flat ribbon  with a plug. Has anyone else had this issue - any suggestions on how to fix such  a simple issue as a thermostat replacement at a reasonable cost?
Thanks


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## Guest

RE: DuoTherm Thermostat replacement problem

welcome to the forums ronwsi ,, i have only seen this once ,, but it was in a newer model rv ,, and the only reason the thermo was replaced ,, was due to mice ,, they chewed the ribbon cord ,, and the front a/c unit would not work ,, let me ck my catalogs ,, i may just have a replacement or another alternative to u'r prob ,, Btw the thermo i replaced was also ,, replaced by another one ,, but it was a plug and play type deal ,, i'll let u know ,,,  :approve:


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## vanole

Re: DuoTherm Thermostat replacement problem

RonWSI,

I PM'd you a solution tha worked for me.  Please let me know if you have trouble locating the web pages I speak of.

V/R
Jeff


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## goeers2001

RE: DuoTherm Thermostat replacement problem

Please let me know what has worked for anyone. Mine needs both units that can tell.Thanks


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## RonWSl

Re: DuoTherm Thermostat replacement problem

Jeff. thanks for the info,,,don't think your ideas will work with my problem,,,i was told by a mechanic that the theromsat is basically trashed - having no luck finding a replacement - several phone calls to rv salvage yards without luck,,,,adding to the problem, in one of the calls was also told that I couldn't just replace the rear thermo and control unit (which at over $350 from dometic I wouldn't do anyway, but would have to replace controls and stats in the front as well,,,,seems ridiculous that an AC manufacturing  company wouldn't carry a stock of replacement thermostats if they are aware that other generic thermostats won't work with their models....still hoping for a resolution at a reasonable cost, or may have to bite the bullet and just replace the whole ac unit,,,,all for a $20 part :angry:


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## vanole

Re: DuoTherm Thermostat replacement problem

RonWSI,

Know what you mean on no supply support.  I would give it a shot on cleaning the button contacts just to be sure.  I was told the same thing when it happenned to me.  Another option is that one site in my PM there is a guy who will rebuild your thermostat (got to be cheaper than 350 clams).  I also think dinosaur (SP) electronics will rebuild it for you also.  

I also agree with you about dometic leaving a bunch of folks hanging with the 4 button thermostat.

Also if you canot find the guy's post I mentioned try googling "Dometic Comfot Control System" do the quick read of the links and you will see his where he states I rebuild thermostats.

V/R
Jeff


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## whendrix

RE: DuoTherm Thermostat replacement problem

I rebuild DuoTherm thermostats and have a few of the (Harper Wyman) 310 5356 004.  I also have the previous series and the 4 button series.  I also have upgrade kits to 5 button from either.  email me at whendrix@aol.com.   William Hendrix


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