Dometic fridge RM2652 tripping thermal sensor

rvman69 wrote:
John, Thanks for the photos and information. Well I have had it plugged in for 6 hours. All of the lower pipes I can reach 6 thru 12 on your diagram are still cold to the touch. So there is no movement in the cooling unit is this correct? The flue is so hot all I can do is tap it with my finger with out get burned or blistered. I am pretty sure it is not working at all. I got a feeling I am going to be ordering a cooling unit. I know it takes a long time for it to start cooling down inside fridge and freezer but it should start circulating in 6 hours correct? Just as a note after 6 hours the temp in the freezer and fridge did not drop at all. Thanks

Hi,

As you see from my data, point 10 on the cooling unit started at 53F, and approx 1 1/2 hours later, point 10 was close to 106F on a working fridge with only 1 gallon of ambient temp water inside the fridge.

At approx 5 1/2" hrs later from starting, the yogurt cup of water in the freezer was frozen solid. The cup is about 1 1/2" deep water.

The above readings are from cycling on and off of the electric heating element from the control system.

If you have been on for 6 hours non-stop heating element and point 10 is still cold, well, the fluid is not circulating.

Point 1, which is the sleeve of the electric element, gets up into the 600 to 700F degree area. The boiler tube with moving fluid, I suspect, is less but still very hot and could be in the 450 - 550 range. The metal shield over the insulation gets convection heating, which is where the thermal disk switch sensor is mounted and shuts the system down. I am not sure what setpoint that trips at.

It could also have partially blocked flow internally and just now starting to leak. If the fridge is run off level for a good period of time or multiple smaller amounts of time, the fluid gets burnt and starts clogging until there is no flow. It's an accumulative issue that once the fluid is burnt, that area will never get better unless the coil is cleaned out during a rebuild.

Again, curious about what Doug will say, but the test so far does not look good; your cooling unit is not working and very possibly leaking.

I will say this, if you change the cooling unit, plan on changing the electric element at the same time. They are not that expensive, and they do go bad over time, they short out inside the element and trip any GFIC the camper is ever plugged into.

John