Dometic RM2453 freezes everything, only on propane

[mhenry79]

Hi, I have a Dometic RM2453 with manual controls (piezo lighter) which works perfectly in AC and DC modes, but on propane everything freezes within a few hours. Doesn't matter if it's 40 or 80 outside, thermostat set to min or max. If this were an electronic system with a solenoid and thermistor I would have some idea what to troubleshoot, but I don't understand how this manual system senses when to stop cooling. Any suggestions?

Also, I'm confused on how it would work during proper operation -- would I need to be there to hit the piezo switch again when it was time to restart cooling? Seems like the pilot would stay lit and something would demand more propane when needed?

[mhenry79]

Thanks! Hopefully that is good news, I'll try through the front panel first.

[Chris_Bryant]

I should amend my answer- I think the thermostat is directly behind the top front panel- you won't need to pull the refrigerator completely, just 4-5".

[mhenry79]

Thank you for the diagram! I will post back in a month or so... will be out of town before I can dig that far into it.

[Chris_Bryant]

It's at the top rear- the controls hook to it via a shaft- the thermostat is #56 on this (click for full size)



You pretty much have to pull it.

[mhenry79]

Old-Biscuit, thank you for the link to the manuals! Between your explanation and the manual, now I get it with the low/high flame. I looked at the jet and burner and they are unobstructed.

Chris, do you know where the pictured assembly is located on the refrigerator? I have easy access to the burner but the small hard lines go left and up the back under a bundle of wires. Is it accessible without removing the whole refrigerator?

Thank you,

Mike

[Chris_Bryant]

If the thermostat is cycling on electric but not gas, it sounds like the o-ring on the bypass screw is bad or missing-



There is a tiny o-ring on the small end of the bypass screw- if this is bad, you will get full flow of LP at all times.

[Old-Biscuit]

Your model of Dometic uses ONE thermostat (Knob B) for temp control whether on 'GAS' (propane) or on 'Electric'

Only difference is when using Electric the thermostat will turn element ON/OFF as need to maintain temp based on whether thermostat is set (OFF to MAX)

When using Propane the thermostat will cut the burner back to bypass which is a very small flame.
IF thermostat was set to OFF the small bypass flame would run continuously
Flame should NOT go out unless you turn fridge OFF (Knob A)

If fridge can NOT go into bypass flame then it will over cool.....could just need good cleaning of burner area.

You can find and download manual for your RM2453 Model CLICK---HERE
Just type in RM2453