help frig problem

Augustpilot · 08-19-2016, 09:01 PM

2017 rockwood ultra light. Have a Dometic dmr/doc series 7 frig. It has selection for lp or auto which uses Elric or propane. Has 3 blue lights. That let you select low med high for temp. They also serve as fault lights. Just arrived Friday night. Seaside OR. Have 2 lights flashing. Which says he problem with the thermostat Needs service. There is no help around and it is weekend. Cannot find reset outside on back of frig. Trying to search on Internet. No answers yet. If anyone has suggestions. Send them over. Thanks

GOTTOYS · 08-19-2016, 09:16 PM

I may not be much help but you might try turning everything off wait a minute or so then turn it back on. Wish I could be more help. Good luck!

jbhodj · 08-19-2016, 09:30 PM

While I don't have your exact model i had many issues with a Dometic fridge. It would run on propane but not electric. So I suggest switching over to propane first. Make sure you bleed the air thru stove before switching. If it runs on propane and not electric then the problem cud be anything but first place to look is outside under the vent cover there shud be a black cover that you can remove. Under that is a circuit board and a small 120v 5 amp fuse. This maybe blown and needs replaced. Also on the flu there could be a thermal coupler with a tiny little reset button in middle of that that has popped. Pressing that little reset button if protruded will reset it. If it does it again then you have a bad thermal coupler and you have to unplug it and jump the wires plugged into it with an ATC spade fuse. This is temporary fix only to get you by.

Sent from my iPhone using Forest River Forums

jbhodj · 08-19-2016, 09:35 PM

Continued. If it runs on propane and not electric then I'm afraid you may have a bad unit or element that heats up the anhydrous to start the cooling. If you can get it to run on propane let it crank on that for awhile and then after its cooled down some switch over to electric. I was told that just starting out on electric some Dometic unit elements heat up to fast blowing that little fuse and shutting down.

Again try propane only first and see what happens. If you have a tester make sure you have power on receptacle under vent cover. Look for that little fuse and check it.

Sent from my iPhone using Forest River Forums

**Bama Rambler** · 08-21-2016, 06:32 AM

If you haven't already gotten it figured out. That error message is actually the overheat thermostat (hi temp cutout).

If you look at the manual you'll see what's called a thermofuse in the drawings. This is the device they're calling the Overheat Thermostat. If you know how to use a multimeter, turn off all power (12 & 120 volts), unplug one of the wires and test the resistance across the device. It normally reads zero ohms. It's most likely open (∞ infinite). It could be that the burner/element has overheated the flue, or it could be that the cutout failed prematurely.

raytwntrvlr · 08-21-2016, 07:10 AM

As the owner of a "blue light special", I read this post yesterday and saw more replies. Some not very helpful!!

Glad someone came along who knows what is happening. A real bummer to have troubles with the refrigerator.

Hope you can get things working.

Happy Camping

Augustpilot · 08-21-2016, 01:15 PM

Checked the ohm reading across the thermofuse, have a reading showing switch closed, the back button appears to be all the way out, cannot push back in. Maybe the thermofuse is good for one time. When get this fixed, maybe need to install extra fans in back of frig as others have done for extra cooling

**Bama Rambler** · 08-21-2016, 02:04 PM

If it's reading zero ohms (or very close) then it's good and there's another problem. Most likely with control board or display.

If it's good, you can try removing all power for 30 minutes and seeing if it resets the lights.

Camperstewart · 08-22-2016, 06:58 AM

If problems continue after you get fixed as I to had the double flashing blue lights they replaced a few parts that would normally cause this problem and yet I still had the same issue after a week, found out we were getting low voltage from the converter. They replaced the converter and we have not had a problem afterwards
Good luck

**Bama Rambler** · 08-22-2016, 12:03 PM

Good info Stewart. I didn't think about low voltage on the DC side.

Augustpilot · 08-26-2016, 11:44 PM

There are two things two protect against overheat, a thermo fuse in flue that will pop like a breaker to cut power, also a line off one post on the thermo fuse that goes to another thermo fuse, it is a resistor. It is secondary backup. When it goes, cannot reset but have to replace. In my unit the resistor fuse went first. Replaced and working well. Thanks for all the suggestions.

You may also like: