Fridge Propane Problem

[dbawden]

Dometic fridge works on battery and 110. Reset the fridge. Inspected the burner and cleaned it. Turned on propane and it lit. Fridge thinks everything is fine but it’s not. Will not chill at all on propane.

Posts here describe this as just being a pilot light. An ignition sound of the burner should be heard. There is no second ignition sound.

Any links or thoughts would be appreciated.

[Donna D.]

Originally Posted by dbawden

Dometic fridge works on battery and 110. Reset the fridge. Inspected the burner and cleaned it. Turned on propane and it lit. Fridge thinks everything is fine but it’s not. Will not chill at all on propane.

Any links or thoughts would be appreciated.

How long are you waiting for it to get cold? It can take hours. Is the trailer level? Will neither the fridge or the freezer get cold?

[dbawden]

The trailer is level. Having warm milk the next morning after being on for 15 hours was my first clue something was amiss.

[Sailingmiker]

Did you clean the orifice? My Dometic has lit but not cooled twice now. Each time it didn't cool while lit I shut it off and cleaned the orifice with alcohol and then it would cool fine for a few weeks. Now trying to determine cause for the orifice becoming restricted by a black oily substance.

[rubicon327]

Originally Posted by Sailingmiker

Did you clean the orifice? My Dometic has lit but not cooled twice now. Each time it didn't cool while lit I shut it off and cleaned the orifice with alcohol and then it would cool fine for a few weeks. Now trying to determine cause for the orifice becoming restricted by a black oily substance.

Black oily substance sounds like you may have contaminates in the propane. Some info online. Where are you filling your tanks?

[dbawden]

So…is this correct? when I turn on the propane option it first starts the pilot light. Secondly, once it is happy with the pilot light it starts an actual burner whose heat is used in the refrigeration process? From what I’ve read, there is a noticeable sound when the burner kicks on. Correct?

BTW: an individual who will remain unnamed has described this condition I am experiencing as a “wimpy flame syndrome” and the solution is alcohol. At my age, that’s to be expected.

[dbawden]

Yes. I cleaned it out with a pipe cleaner but will next do a more thorough cleaning with alcohol and see if that’s the trick.

[rubicon327]

Originally Posted by dbawden

So…is this correct? when I turn on the propane option it first starts the pilot light. Secondly, once it is happy with the pilot light it starts an actual burner whose heat is used in the refrigeration process? From what I’ve read, there is a noticeable sound when the burner kicks on. Correct?

Incorrect. There is no pilot. There is only one flame that varies in intensity depending on the refrigerator thermostat setting.

Older RV fridges did have pilot lights but not the fridges in Escape trailers that have an electric igniter that lights the single burner flame.

[SageRpod]

Originally Posted by dbawden

Dometic fridge works on battery and 110. Reset the fridge. Inspected the burner and cleaned it. Turned on propane and it lit. Fridge thinks everything is fine but it’s not. Will not chill at all on propane.

Posts here describe this as just being a pilot light. An ignition sound of the burner should be heard. There is no second ignition sound.

Any links or thoughts would be appreciated.

When you say you reset the fridge, do you mean the thermal reset switch on back behind the shielding? I had to reset there when I had problems earlier this summer from the trailer not being level enough.

[MVA]

There are only a couple of places where black tar material can originate. Have you examined the hose from the regulator to the trailer copper lines? I would consider it may have degraded after 7 years.

[Bobbie54]

Is it warm inside the trailer when the fridge isn't getting cold?

with mine I can hear the spark as it ignites after the burner has been off for awhile. But there could be differences in models from past years and in other trailers.

[JohnK]

Originally Posted by dbawden

Yes. I cleaned it out with a pipe cleaner but will next do a more thorough cleaning with alcohol and see if that’s the trick.

The orifice should never be cleaned mechanically such as inserting anything into it. MEK or some strong solvent of some kind is appropriate.

Just one more thought apart from the orifice: I have sometimes had to tap on the plumbing/valve area behind the fridge from the exterior access opening to get the valve to open so gas flows. I have also found that bicycle chain spray lubricant keeps that valve lubricated enough to where it does not require tapping to vibrate it open.

Bonne Chance!

John

[Sailingmiker]

Lets back up a bit to clarify how the burner works. When the refrigerator is started on propane several things happen: Propane is inserted into the burner by way of the orifice at the end of the copper gas supply line. A Piezo lighter sends a spark to the burner which ignites the propane. A thermocouple senses heat and allows the propane to continue to flow to the burner. The heat from the burner is used in the cooling process. If there is not enough heat the freezer may cool as it is first in line but the fridge doesn't. So you may see a flame at the burner even though the fridge doesn't cool.
The burner is likely not heating enough because the orifice is clogged/restricted. Cleaning the orifice with alcohol and compressed air solved the cooling issue for me. At least until it clogged again.

[LeonW]

you might also want to check your propane pressure using a manometer. my recollection is that it should be about 11 inches of water column. Long ago I had some problems with the fridge that were solved by replacing the regulator.

[Ron in BC]

Here's my take and experience.

Scamp 13; two years and zero problems

E19, Gen 1: 5 years and lot's of problems

E21C, Gen 2; 4 years and zero problems

Maybe that indicates that some models are less trouble than others.

I went through the orifice cleaning routine many times on the E19. Sometimes it worked and sometimes it didn't. A couple of times there were loose small bits of black carbon. I don't really think that they were restricting the flow of gas.

Many times I suspected that the gas valve was the problem. Once I undid the intake line, thereby relieving any back pressure on the valve and all was well again. Sometimes I just gave it a whack and sometimes I relieved back pressure. Easy to do, turn off the gas at the tank. Light the stove and let it die.

I have to say, love the fridge in the 21. Because of the 19 experience I appreciate it even more.

Ron

[dbawden]

Update: cleaned the tube with alcohol and still no second level of burning. I assume the tube everyone is referring to is this one. Or is the orifice for cleaning the vertical pipe above the pilot light that is enclosed in the chimney?

https://downloads.intercomcdn.com/i/...leaning-03.jpg

[rubicon327]

Originally Posted by dbawden

Update: cleaned the tube with alcohol and still no second level of burning. I assume the tube everyone is referring to is this one. Or is the orifice for cleaning the vertical pipe above the pilot light that is enclosed in the chimney?

https://downloads.intercomcdn.com/i/...leaning-03.jpg

That’s the burner tube. Just upstream (to the left) of the burner tube where the propane shoots in there should be a removable fitting with a very tiny hole. That is the orifice. Remove it, soak it in alcohol and replace. I reattached your graphic with the orifice circled. Do not try to mechanically clean the orifice as it can be damaged and I’ve heard stories of it being dislodged from the fitting and then you are in a real bind.

[dbawden]

Originally Posted by rubicon327

That’s the burner tube. Just upstream (to the left) of the burner tube where the propane shoots in there should be a removable fitting with a very tiny hole. That is the orifice. Remove it, soak it in alcohol and replace. I reattached your graphic with the orifice circled. Do not try to mechanically clean the orifice as it can be damaged and I’ve heard stories of it being dislodged from the fitting and then you are in a real bind.

Thanks. That clarifies the culprit perfectly.

[dbawden]

Update: pulled the correct propane orifice, cleaned with alcohol, and that solved the problem.

Many thanks to the diligent members here that helped me especially Sailingmiker, Rubicon and Ross. You provided the key elements to solve the problem.

The freezer registers a nice 24 degrees and my wife is very happy…again.

[rubicon327]

Originally Posted by dbawden

Update: pulled the correct propane orifice, cleaned with alcohol, and that solved the problem.

Many thanks to the diligent members here that helped me especially Sailingmiker, Rubicon and Ross. You provided the key elements to solve the problem.

The freezer registers a nice 24 degrees and my wife is very happy…again.

Glad to hear it is now working well. The freezer will drop in temperature first and then the fridge will follow. That is typical because the working fluid runs through the freezer evaporator first and then through the fridge evaporator which are in series. Absorption technology might seem antiquated to some but as an engineer I find it to be a fascinating process.