I just realized I've been running my Dometic fridge on propane when I camp even though it should be running on AC when I'm plugged in.AC is plugged in.Propane tanks are on.Dometic switch is in the auto position.I keep getting the try again light when I'm starting the fridge.So I run the propane to the stove and let it burn for a minute to prime the line, I guess.Then the fridge starts to work.No, I think I've just answered my own question.The fridge always requires propane to operate, but switches between 12V and AC.So if I am hooked to AC the auto will choose the AC.If the AC isn't hooked up the auto will choose DC.Regardless it will always use propane?

It should only use propane when no 120VAC is present.I just recently had the same issue and here is what I found:1st I checked the plug in the back of the fridge and the voltage was present there. Next I took off the black cover off the circuit board and checked the fuses and both were good. Next I checked where the 120V Ac plugs onto the circuit board and found that the spaded plug was not completely pushed on. When I pushed on it, it snapped in. I then plugged the AC plug back in and turned on the fridge and it worked on AC as it should.If all fuses are good and the connections are all tight the next thing to check is the heating element with an ohm meter. I think it's suppose to have about 41ohms if the heater rod is good. Also there should be Voltage across the pins where the heater rod is connected to the circuit board. If no voltage is present there, but all else checks out ok then the board may be bad. Some RV parts/shops have a circuit board tester which I would recommend before replacing the board.

LaunchnRetrieve wrote:Regardless it will always use propane?No, that's not normal, if it's both a gas and AC fridge. As said above, take off the back panel and make sure the ac plug is in. Push the Auto/gas switch a few times.. maybe it's stuck. Try turning the unit off and on a few times.Mine got stuck on ac once, I finally had to pull its ac feed plug to get it to go to gas. It's plugged back in and working ok. Sometimes they get confused!

No it should not always run on propane. When the refer is set it should run on AC if available and run on propane when not available. Refer should be set on "auto".Start by checking the refer receptacle in the exterior access. Use a known good appliance such as an electric drill. Wiggle the cord body in the receptacle while operating the appliance to see if it cuts out.Check the fuse holder on the circuit board in the refer outside access.Turn off power to the refer or the rig. remove the circuit board and inspect the back of it for burnt places. If you see any replace circuit board with Dinosaur Electronics replacement.

OK, thanks for the tips.And the clarification.

LaunchnRetrieve wrote:The fridge always requires propane to operate, but switches between 12V and AC.So if I am hooked to AC the auto will choose the AC.If the AC isn't hooked up the auto will choose DC.Regardless it will always use propane?No. First off, there is (usually) no DC mode in these fridges, only AC, Propane and Auto. Few have DC mode, but most of them don't.Assuming everything is wired as it should -If you switch to AC, it will run on AC only. Propane will not be used.If you switch to Auto, it will choose either AC or propane. Better don't use the Auto.If you switch to Propane (or Gas, or whatever is written on the panel), it will work on propane and will also draw some DC from battery to operate the thermostat. In absence of Dc (low battery, for example) it will attempt to fire up propane, you'll hear ignition clicking a few times, and then it will display error message.

Dometic Alwasy Runs On Propane? | Good Sam Community

13 Replies

enblethen
Nomad
Dec 30, 2015
Default to propane , No. You can manual set it to propane.
dougrainer
Nomad
Dec 30, 2015
kampinguru wrote:
Anyone know if it is possible to switch the fridge around so it runs on propane by default and will switch to electric if the propane runs out? I get my propane for free and would rather run it on propane but have electric backup.

No, but HOW can you get LP for free??????? LP costs someone something, it is not pulled out of the ground. So, while it may be free to YOU--- someone is paying for it. The 120 volt operation in electricity cost is pennies per day. Doug
kampinguru
Explorer
Dec 30, 2015
Anyone know if it is possible to switch the fridge around so it runs on propane by default and will switch to electric if the propane runs out? I get my propane for free and would rather run it on propane but have electric backup.
enblethen
Nomad
Dec 29, 2015
OP:
please post model of your refer. I doubt whether it is a three way.
mkirsch
Nomad II
Dec 29, 2015
My 3-way fridge is plugged into a GFCI outlet in back. Maybe the GFCI is tripped?
Gjac
Explorer III
Dec 29, 2015
wrgrs50s wrote:
It should only use propane when no 120VAC is present.

I just recently had the same issue and here is what I found:
1st I checked the plug in the back of the fridge and the voltage was present there. Next I took off the black cover off the circuit board and checked the fuses and both were good. Next I checked where the 120V Ac plugs onto the circuit board and found that the spaded plug was not completely pushed on. When I pushed on it, it snapped in. I then plugged the AC plug back in and turned on the fridge and it worked on AC as it should.

If all fuses are good and the connections are all tight the next thing to check is the heating element with an ohm meter. I think it's suppose to have about 41ohms if the heater rod is good. Also there should be Voltage across the pins where the heater rod is connected to the circuit board. If no voltage is present there, but all else checks out ok then the board may be bad. Some RV parts/shops have a circuit board tester which I would recommend before replacing the board.
When this happened to me I noticed a slight clicking noise in the eyebrow when I would slide the button from propane to auto. It turned out to be the spade plug the Walter referenced above. I cleaned it with an eraser and plugged it back in and it has been working well for the last 3 years.
12thgenusa
Explorer
Dec 28, 2015
Always needs DC to operate circuit board and monitoring system. If AC available (in auto mode) uses AC heat element to heat boiler. If no AC available, uses propane flame to heat boiler. If not in auto mode it will only operate with propane.

Sounds like in auto mode it is not sensing the presence of AC or AC is not actually present for some reason.
starcraft69
Explorer
Dec 28, 2015
wrgrs50s wrote:
It should only use propane when no 120VAC is present.

I just recently had the same issue and here is what I found:
1st I checked the plug in the back of the fridge and the voltage was present there. Next I took off the black cover off the circuit board and checked the fuses and both were good. Next I checked where the 120V Ac plugs onto the circuit board and found that the spaded plug was not completely pushed on. When I pushed on it, it snapped in. I then plugged the AC plug back in and turned on the fridge and it worked on AC as it should.

If all fuses are good and the connections are all tight the next thing to check is the heating element with an ohm meter. I think it's suppose to have about 41ohms if the heater rod is good. Also there should be Voltage across the pins where the heater rod is connected to the circuit board. If no voltage is present there, but all else checks out ok then the board may be bad. Some RV parts/shops have a circuit board tester which I would recommend before replacing the board.

This is the best advice you will get. The order of trouble shooting is right on spot.
Almot
Explorer III
Dec 28, 2015
LaunchnRetrieve wrote:

The fridge always requires propane to operate, but switches between 12V and AC.
So if I am hooked to AC the auto will choose the AC.
If the AC isn't hooked up the auto will choose DC.
Regardless it will always use propane?

No.
First off, there is (usually) no DC mode in these fridges, only AC, Propane and Auto. Few have DC mode, but most of them don't.

Assuming everything is wired as it should -

If you switch to AC, it will run on AC only. Propane will not be used.

If you switch to Auto, it will choose either AC or propane. Better don't use the Auto.

If you switch to Propane (or Gas, or whatever is written on the panel), it will work on propane and will also draw some DC from battery to operate the thermostat. In absence of Dc (low battery, for example) it will attempt to fire up propane, you'll hear ignition clicking a few times, and then it will display error message.
LaunchnRetrieve
Explorer
Dec 28, 2015
OK, thanks for the tips.
And the clarification.