Any Dometic fridge gurus? (1 Viewer)

Bustup15

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In a previous post I mentioned my RMDT8555 was periodically resetting and rebooting irrespective of what power source was connected. When this happened it always reverted to gas.

I eventually removed the front control panel but I can't see anything obviously wrong or burnt out.

On reconnection it would not stay turned off i.e. It immediately powered back up.

As a result I left the board disconnected whilst it was in storage - see a further post to come about the main motorhome control panel and isolating 12v.

Im not sure if the 2 faults are related or not!

Back to original post.

Going away for a couple of days so reconnected the board. Whilst away the issue of rebooting and always selecting gas option seems to have solved itself. 😁. On mains for 24 hours, driving on 12v, parked up on gas all auto switching correctly.

I didn't try powering the fridge off whilst away but on return that fault of auto switch on is still present. I've found the relevant fuse on the EBL and am using that to isolate the fridge to prevent power drain when not in use.

I've looked at the cost of a new control panel circa £300 🙄 although no one seems to stock them.

Do you think this is the issue or is there something else going on?
 
Jan 2, 2015
2,473
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Burstner Solano t725
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A few years back, I had to replace the PCB on my identical Dometic.
As you say trying to source one can be a bit expensive so I approached it from a different angle by changing my search from "Dometic RMDT8555 PCB" to using the actual "serial no" etched on the faulty PCB. When Google showed the results, I selected 'images' at the top of the results page and compared against my PCB and found one considerably cheaper.

Unfortunately I'm not in a position to tell you who I bought it from as I'm away from home.

Incidentally there are both the Service and the Installation manuals for the Dometic 8xxx series in the Resources Section.

Good Luck.
 
Aug 6, 2013
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Incidentally the control PCB is at the rear behind the lower vent. It's worth removing it and checking for corrosion and damage.
 
Oct 10, 2018
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Bustup15 There was someone who had a problem with the controls on a RMS8551 (Would not turn off) and it was suggested that they tried drying the control panel with a hair drier , which worked. Maybe there is damp in your control panel and it may be worth trying this , if it goes wrong again .
 
Jun 3, 2021
317
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Hymer B680
I had a problem with my RMD8555 fridge you can't buy the pcb's for them anymore, I sent my pcb to Speak Electronic repair service and he repaired some bad joints for £40.00 incl postage. His No. is 0161 637 1023, by the way a new fridge is circa £3k hope this helps,

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Bustup15

Bustup15

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Finally solved the issue :roflmto:

Ordered a new control pcb (the external unit) swapped out the old unit and it all works!

Mains, gas and 12v all autoswitching and I can even turn the fridge on and off via the front control panel.

No more having to pull the fuse when it's parked up (y)

Incidentally no obvious damage or corrosion on the old unit. Might open it up and see if there's anything repairable and use it as a spare?

20230414_115745.jpg
 

tonka

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Finally solved the issue :roflmto:

Ordered a new control pcb (the external unit) swapped out the old unit and it all works!

Mains, gas and 12v all autoswitching and I can even turn the fridge on and off via the front control panel.

No more having to pull the fuse when it's parked up (y)

Incidentally no obvious damage or corrosion on the old unit. Might open it up and see if there's anything repairable and use it as a spare?

View attachment 739028

May have no connection at all but seeing that label ref a polyswitch, there was an issue once with Autotrails and a faulty batch of polyswitches in the sargent units. May be worth swopping that out just in case. 👍
 
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Bustup15

Bustup15

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May have no connection at all but seeing that label ref a polyswitch, there was an issue once with Autotrails and a faulty batch of polyswitches in the sargent units. May be worth swopping that out just in case. 👍
The polyswitch is internal I assume?
 
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Bustup15

Bustup15

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Anyone ever taken one of these units apart?
 
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Bustup15

Bustup15

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Finally solved the issue :roflmto:

Ordered a new control pcb (the external unit) swapped out the old unit and it all works!

Mains, gas and 12v all autoswitching and I can even turn the fridge on and off via the front control panel.

No more having to pull the fuse when it's parked up (y)

Incidentally no obvious damage or corrosion on the old unit. Might open it up and see if there's anything repairable and use it as a spare?

View attachment 739028
And a few weeks later the original fault has returned, unable to turn off the fridge at control panel - well pissed would be mild!
 

Lenny HB

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Oct 18, 2007
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Finally solved the issue :roflmto:

Ordered a new control pcb (the external unit) swapped out the old unit and it all works!

Mains, gas and 12v all autoswitching and I can even turn the fridge on and off via the front control panel.

No more having to pull the fuse when it's parked up (y)

Incidentally no obvious damage or corrosion on the old unit. Might open it up and see if there's anything repairable and use it as a spare?

View attachment 739028
They are not serviceable the PCB is potted I've had one apart.
 

Lenny HB

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Oct 18, 2007
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Agree but the new one now has the same fault 🤷‍♂️
At least it's under warranty if it is that may have been a white herring and the fault is in the control panels.

Most of the problems with those units were with the eairler version without the polyfuses.

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Bustup15

Bustup15

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And a few weeks later the original fault has returned, unable to turn off the fridge at control panel - well pissed would be mild!
Still waiting for supplier to resolve this issue. In the meantime to resolve the issue of being unable to turn fridge off without pulling a fuse I've fitted an additional isolator switch to the vent panel above the oven unit. It's all in black and virtually invisible.
 

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