Dometic fridge behaviour and temperature analysis - RM8551

[Windymountain]

Our Escape 19 is 7 years old and on our last trip the fridge misbehaved. The fridge was set at the highest (5 lights) but didn’t cool down at all on propane. It worked on electricity when we had it. When I got home and researched the topic, I found lots of information (and complaints) about this fridge. I found some excellent resources related to cleaning the burner and the orifice. I removed them, blasted them with air and reinstalled them. This maintenance task solved the problem. I’m quite sure the prior owner had never performed any maintenance on the fridge and I definitely blew out some rust particles.

Then I decided to see how the fridge behaves on all 5 settings on both gas and electricity. The fridge only had a few items in it and the outside temperate was around 18 Celsius (65 Fahrenheit) during the day. Here’s the chart. It’s quite interesting. Id love to do this again on a hot day but that will have to wait till next summer.

I was curious how much the settings affect the temperature and now I know.

[KirkB]

I have the same 8551 reefer as you.

I first encountered the same non-cooling problems with propane as you a few years ago, and have posted a few responses to this forum.

Here are my observations - between 20*C and 25*C, the fridge can work like a champ, but if the temp goes up closer to 30*C, then you will have >5*C fridge temps, whether you are on propane or AC.

I have experienced trips where the fridge refused to cool on propane, even on cooler ambient temps. Most times the fridge lights, but refuses to cool in warm weather. I have always been able to fix this by removing and soaking the burner in alcohol. I usually find a bunch of brown rusty grit blocking the burner orifice. Cleaning the burner usually gives me a solid blue hot flame that can make the reefer work. My other theory is that rough roads can loosen grit in the propane line. Your fridge can work fine on your driveway, but after a day's drive, some bit of grit has plugged up the fridge burner.

Cleaning the fridge propane burner has become part of our pre-departure checklist.

[Bill and Earline]

WindyMountain,

That is a well thought out chart. Thanks.

For those of us who have dealt with similar fridges for years, some of us think it is also helpful to unclip the thermistor from the aluminum fins and let is hang in mid-air. The concept being that instead of reading the temp of the cooling fin (cold), it would then be reading the temp of the air (less cold). Thus the "dangling thermistor" might improve cooling.

Also, some have thought that putting something frozen from the freezer compartment might help cool the fridge. If that frozen item is anywhere near the thermistor, it will chill the thermistor and turn off the fridge. If you want to encourage the thermistor to stay on, put something room temperature near the thermistor, and the fridge will run more than it might otherwise. Of course it might then freeze your lettuce.