Using a Dometic 8505 Fridge on Gas Only

[Rond58]

I realise that my request is outside of any warranty etc. I have removed my faulty fridge old fridge from my Motorhome and replaced it. I do however still wish to use my removed (old) 8505 fridge only on gas in my off grid garage to keep cool drinks cold. The old fridge works perfectly well on 220 volt power (Spain) but not on 12 volt nor gas. I only wish to have the gas working but due to the electronic configuration this is impossible for me to do without advice and guidance. To make everything the simpliest possible, I am hoping to get advice on how to bypass the electronic working for everything else except to light the pilot light so as to have the gas begin its cooling function. I am very familiare with the older less complicated gas fridges from yesteryear but not these electronically controlled devices. I do not speak Spanish either so any communications with the locals simply result in confusion .

PLease offer some thoughts for me to over come my little ( lol) challenge.

I live remotely in Spain and am far away from skilled labour / recreational vehicle experts.


many thanks in anticipation

Ron Downs

email [email protected]

 

[Kirk]

Here is a link to download a copy of the Dometic Service Manual to use. Over the years I have worked on quite a few RV refrigerators, and I highly doubt that it is possible to make the modifications you wish to do.

 

[John From Detroit]

Did the fridge have an "Auto" mode where it woudl switch to gas if no 220VAC?

You need 12 volts for the control (likely at no more than 5 amps) and NO AC.
Use a filtered regulated supply (Try Ham Radio suppliers)

Since I'm in the USA I get 120 volt supplies
Oh you can also use a battery and solar panel.

https://www.jameco.com/shop/keyword=12V-10-Amp-DC-Power-Supply?srsltid=AfmBOoqI37O-3_PQM6Ce3ttDR6tbuBvNiOrA_ikn-rNyup9QigYcAIlG

 

[Lou Schneider]

If the refrigerator cools in electric mode it implies the control board is functioning. Maybe something is blocking the air tube between the gas valve and the flame - insects are attracted by propane and tend to build nests in there. Or debris has fallen from the flue and is blocking the burner itself. It's fairly small, the overall flame is just slightly larger than a typical pilot light.

The most likely causes for failure of the gas side are not getting a spark at the ignition electrode, a bad solenoid that isn't opening the gas valve or a failure of the the sensor that tells the control board the flame is lit. This is often the same electrode that supplies the spark to ignite the flame.

You'll have to replace the electrically controlled gas control valve and thermostat with mechanical units to make this gas-only. Probably simpler just supply the small amount of 12vdc the control board needs so it can do it's thing. Or find out why the gas isn't reaching the burner.

 

[Rond58]

Here is a link to download a copy of the Dometic Service Manual to use. Over the years I have worked on quite a few RV refrigerators, and I highly doubt that it is possible to make the modifications you wish to do.

Thank you so much for the service manual . This may help. Have a great day out there

 

[Rond58]

Did the fridge have an "Auto" mode where it woudl switch to gas if no 220VAC?

You need 12 volts for the control (likely at no more than 5 amps) and NO AC.
Use a filtered regulated supply (Try Ham Radio suppliers)

Since I'm in the USA I get 120 volt supplies
Oh you can also use a battery and solar panel.

https://www.jameco.com/shop/keyword=12V-10-Amp-DC-Power-Supply?srsltid=AfmBOoqI37O-3_PQM6Ce3ttDR6tbuBvNiOrA_ikn-rNyup9QigYcAIlG

Hi there, and thanks for the feedback. I actually had a proffessional guy swop the fridge out and he didn't want to give me back my old non working fridge but I insisted. So sadly I can't even ask him to help me out as I'm sure he wanted it for himself to do similar to what I want to do . To clarify furher.... I managed to clean a few connectors on the rear of the fridge and now at least the control panel lights up, at shows all the respective possibilities for connection ( connected to a spare 12 volt car battery I have. Sadly when I select either AEG, 12 volt or GAS , the fault light flashes constantly without sound alarm. I'm thinking that possibly I need to also connect the following ( D+, and S+), before the fridge will work but I'm hoping that is not the case. I can send you pictures of the PC board if this will help?

 

[Rond58]

Hi there, and thanks for the feedback. I actually had a proffessional guy swop the fridge out and he didn't want to give me back my old non working fridge but I insisted. So sadly I can't even ask him to help me out as I'm sure he wanted it for himself to do similar to what I want to do . To clarify furher.... I managed to clean a few connectors on the rear of the fridge and now at least the control panel lights up, at shows all the respective possibilities for connection ( connected to a spare 12 volt car battery I have. Sadly when I select either AEG, 12 volt or GAS , the fault light flashes constantly without sound alarm. I'm thinking that possibly I need to also connect the following ( D+, and S+), before the fridge will work but I'm hoping that is not the case. I can send you pictures of the PC board if this will help?

Regarding the 12 volt connection simply to light the control panel...... Can I use a smal domestic 220 volt to 12 volt transformer?

 

[Rond58]

If the refrigerator cools in electric mode it implies the control board is functioning. Maybe something is blocking the air tube between the gas valve and the flame - insects are attracted by propane and tend to build nests in there. Or debris has fallen from the flue and is blocking the burner itself. It's fairly small, the overall flame is just slightly larger than a typical pilot light.

The most likely causes for failure of the gas side are not getting a spark at the ignition electrode, a bad solenoid that isn't opening the gas valve or a failure of the the sensor that tells the control board the flame is lit. This is often the same electrode that supplies the spark to ignite the flame.

You'll have to replace the electrically controlled gas control valve and thermostat with mechanical units to make this gas-only. Probably simpler just supply the small amount of 12vdc the control board needs so it can do it's thing. Or find out why the gas isn't reaching the burner.

Thanks for the feedback and support. I like your changing of the electrically controlled gas control to a manual one. \could guide me to a web site that shows what \i need .. \thanks again ( smiley face)

 

[John From Detroit]

Thanks for the feedback and support. I like your changing of the electrically controlled gas control to a manual one. \could guide me to a web site that shows what \i need .. \thanks again ( smiley face)

Yes but that is what I'd call a "Major" Job

Now plugging the 12 volt leads into a small LiFePO4 that is maintained by a 200 watt solar panel with charge controller..

OR something like a "Jackery" "Solar generator" They call them over here, with a Solar Panel. Easy Peasy. And without AC in the unit should auto-to Gas