Thermocouple Needed

[DaAairstream]

I've gotten my ancient Dometic (RM100) up and running on AC, and plugged in where it should be. Now, I'm tackling issues with running it on gas. It does not want to stay lit. Common wisdom is that it's the thermocouple, and, ordinarily, that would be easy enough. But, I've been told it's a discontinued part number for which there is no substitute.

Anyone know where to get an old item like this, or what I can do to change to a more modern valve with a different thermo couple? I surely can't see replacing a working unit for the lack of a thermocouple, or replacement safety valve.

As with past questions, all help is appreciated.

Thanks.

[TG Twinkie]

I bought a universal one at the hardware store. It works just fine. Just try to find one close to the same length as the existing unit. Mine is a little long but it works.

[4RXLA]

If you are trying to light it from inside the fridge by pressing the knob in you will never get it to stay lit. After turning the knob in the fridge to gas I go outside, open the access door and gently press up and hold the red button for 30 seconds to let air purge from the line and then with a butane lighter light the burner. My unit does not have a round access door to the burner, it has a large piece of metal held in by 2 screws. There is a small gap between this piece of metal and the chimney and I have found that the lighter flame pointed in that gap lights the burner without having to unscrew the panel every time. Once lit, I have to keep pressing up on the red button for at least a minute in order for the burner to stay lit. Sometimes as I slowly release pressure on the red button the flame will go out, in which case I repeat the above and wait for the thermocouple to get hot. You could have a clogged burner. They seem to collect rust/debris over time. Low gas pressure will also cause problems.

However, once you get the burner to stay lit, it will stay lit. I ran mine exclusively on gas on my 25 day trip last year. I drove through some real windy areas and the flame never went out while traveling. I prefer to run on electric in the campground but given the age of the unit, I try to minimize the frequency of lighting the burner. Why tempt fate?

[DaAairstream]

Thanks for the responses. I haven't been depending on the lighter from inside. It's just too hard peaking through the little sight hole to confirm when lit. I do work from the outside, so I think it is going to mean a new thermocouple, of some sort from some where. Hopefully, I can find a universal as suggested.

[Wayne&Sam]

I think my wife is hot. Does that make us a thermocouple?

[RickDavis]

Originally Posted by NewbieAndy

Thanks for the responses. I haven't been depending on the lighter from inside. It's just too hard peaking through the little sight hole to confirm when lit. I do work from the outside, so I think it is going to mean a new thermocouple, of some sort from some where. Hopefully, I can find a universal as suggested.

Be aware it may be a metric thread. If the normal universal one won't screw in check out a replacement for one of the blue flame type heaters.


I also light mine from the rear but I put a piezo lighter from a gas grill near the burner to light it while I hold the bypass button.
We had the electric heater in ours quit as we were leaving for Florida. Ran on gas for 2 months with no blowouts.

[GeocamperAS]

Domestic has a web page. They list authorized service centers. Call one or a few. They will know if there is a replacement.

[AirHeadsRus]

RV PARTS OUTLET

Try this and see if it is the right part.

[Excella CM]

There is a small gap between this piece of metal and the chimney and I have found that the lighter flame pointed in that gap lights the burner without having to unscrew the panel every time."

Boy, does that sound familiar!

[DaAairstream]

I've ordered it. Hopefully they really have it in stock. Thanks for the info, I had tried 3 other surplus outlets, but wasn't aware of this one.