Need Different Dometic Heater Thermostat

[B52Bombardier1]

Hello,

I'm on my second poorly designed, two-wire Dometic thermostat. It's on-off switch is poorly designed because the primary switch contact is a metal bar that requires a precise clearance and metallic stiffness to allow contact with the other bar in the circuit. I've bent this small bar a few times to get the thermostat to mechanically and electrically work again but the the metal in the movable bar has a "memory" and it returns to its original, very slightly different shape and the thermostat fails at that point.

So . . . I'm not buying another Dometic thermostat of this type. Does anybody have any suggestions for a similar two-wire thermostat that is more dependable and might even have a temperature gauge built into the face? I'd even go for something battery powered here that is more dependable and modern than what I've been using.

Many thanks,

Rick

 

[Kevin D Pem]

Go to homedepot or Lowes and ask for help.

 

[TheLooks]

Any thermostat that makes a contact on temperature falling or rising will work. It is just an adjustable switch. Strange yours keep failing. I have had thermostats from many years ago working perfectly and probably have a couple now. Put batteries in a cheap Honeywell thermostat and it will make a contact just fine, just need to ohm the connections to see which ones have continuity. I have one of those also I took out of a camper. Cheap little digital Honeywell.

 

[B52Bombardier1]

Hello,

And thanks for the replies. My wife and I are actually camping in northeast Texas and my tools to further analyze and fix this problem are limited. But we are able to use a small portable electric heater to stay warm at night.

I'm going to get to the bottom of this problem and install something different on the wall very soon. I agree this should be an easy upgrade and I will post pictures after we get home with what I come up with for a solution - we head home later today.

Rick

 

[TheLooks]

If your thermostats are failing, it would seem there is to much power going thru them. The thermostats usually trigger a relay to put power to the bigger draws. Low voltage will cause high current. Check your convertor and batteries.

 

[B52Bombardier1]

The voltage was normal the last time I checked. We just got home tonight and I will look at things again this week.

Rick

 

[B52Bombardier1]

Hello,

Well . . . its not the thermostat. I jumpered those wires just like I did for the last remedy and nothing happened with the heating unit. All fuses in the trailer test good and power is good at that panel.

So, off came the outside access panel for some analysis with my multimeter. I cannot find any 12 volt power to the control board and the board has no LEDS that are lit. I actuated the "Reset - Off" switch a few times and still, nothing happened.

It was dinner time and getting dark so I have quit for now. More to follow this weekend.

Rick

 

[TheLooks]

Believe it or not, the 12v power comes from the AC unit. The control box sends it back down. So the problem may be there. There should be blue wires coming into the board at the furnace. It also depends on the furnace.

 

[B52Bombardier1]

I have never had to turn the AC on or off, hotter or colder with this heating unit. It is a completely standalone Atwood model 8520 that is using a Dometic thermostat.

Rick

 

[TheLooks]

Good luck.

 

[B52Bombardier1]

Hello,

As it turned out, it was a crusty, bad 12 volt feed wire connector to the control board way up under the refrigerator. All is good with the heater again.

Rick