Dou Therm 57915.622 won't work.

[Photog101]

I have a 1999 Newmar American Star XL With one roof air (57915.622) and one furnace (I have not found a label on it yet) with a 4 button thermostat, that I just picked up and they didn't work at that time.

At this time neither unit works (A/C or Furnace) but I have power to the thermostat. I believe that I have tracked it down to the electric kit (controller) 3106481.009. 119 AC volts and 12+ volts are at the controller.

I contacted Dou Therm and they do not have parts to repair or upgrade these units. If they had the parts I would be willing to upgrade, but since winter is coming on and I have a disadvantaged veteran who was homeless living in my camper at the preset time, I would like safe heating. Also everything else works on this camper

All I need for now is heat and was wondering if there was a way to run just the furnace without going through the rooftop A/C. I have extensive automotive and truck electrical experience so I feel confident that I could modify it for the winter until Dou Therm gets the correct parts. I'm sure that I would have to change out the thermostat, which is no big problem, if I know which one will work ... probably an older RV analog style.

Any Ideas, since running electric heaters is going to be expensive and I don't like to try and draw 2-1500 watt electric heaters on the 30 Amp service.

Thanx in advance for any help.

[dougrainer]

I am assuming that the wall tstat has NO display? If so, replace the phone type modular 4 wire plugs at the wall tstat and at the AC upper control board first. Corrosion on those modular plugs is the normal cause of NO display. Doug

[ScottG]

A 23 y/o RV furnace is far from safe (I lost a BIL that way). If you're going to have him using it, make sure there's a new Carbon monoxide sensor present.

[dougrainer]

DOMETIC, NOT Duotherm:) I don't know who you talked to, but you CAN upgrade to the 5 button wall tstat and 5 button board on the AC unit. Are you positive you talked to Dometic and not one of those aftermarket companies that pops up on google searches and LOOKS like the company you are trying to find? Duotherm name has not been used in over 35 years even tho they may have the Duotherm logo on the AC shroud. You just need this kit in the link I have provided. The 4 button was discontinued in 2001 and they went to the 5 button. There are NO 4 button Tstats anywhere. Doug

https://pantherrvproducts.com/3310009-000/?sku=3310009.000&gclid=Cj0KCQjwqoibBhDUARIsAH2OpWjyaUzVTwQ...

When you look at the pic in the link, you will see a blue ended wire. THAT is the NEW style freeze sensor and MUST be used. You remove the OLD style freeze sensor which looks like a large button about 1 inch in diameter.

This link shows what it looks like.

https://www.amazon.com/Dometic-3309191009-Freeze-Control-Sensor/dp/B00JF1WC0Q

[garym114]

Don't know what thermostat you are using On the older analog Duo thermostat the yellow wire in the RV wiring harness runs the heater

[Roger10378]

There should be 2 wires(probably blue) from the furnace to the controller. They need to go to the thermostat. The thermostat is just a switch that connects the 2 wires to turn the furnace on and disconnect the wires to turn the furnace off. You can test the furnace by connecting the 2 wires at the controller and the furnace should work. If the furnace works just extend the wires to the thermostat(common and heat) and you should be good to go.