Dometic RMDT 8505 fridge failure.

[monique.hubrechtsgm]

Not cooling when on 230 volts but the display said ok and no red lights. Works on gas and 12 volt engine running and cooling. Very rare of the logic by dometic. Anyway the heating resistance spiral in ammonia gas cylinder does not get heated to raise the ammonia gas temperature cylinder. It should warm rapidly when on 230 volts you can reach by hand by cutting two wire bundlle straps .The fridge cooling starts afther about half an hour if the spiral works. After taking the data a new spiral can be ordered. Age? two years.

[mgnbuk]

Hi Monique,

 

If I recall correctly from conversations with Dometic at the Motorhome Show, their products have a two year guarantee. It may be worthwhile contacting Dometic & explaining the situation - they may offer to help if the unit is just over two years old, but should repair it under warranty if it is just under two years old.

 

Nigel B

 

[Brian Kirby]

monique.hubrechts@gm - 2017-07-25 5:37 PM

 

Not cooling when on 230 volts but the display said ok and no red lights. Works on gas and 12 volt engine running and cooling. Very rare of the logic by dometic. Anyway the heating resistance spiral in ammonia gas cylinder does not get heated to raise the ammonia gas temperature cylinder. It should warm rapidly when on 230 volts you can reach by hand by cutting two wire bundlle straps .The fridge cooling starts afther about half an hour if the spiral works. After taking the data a new spiral can be ordered. Age? two years.

Monique, as the fridge works on gas and 12V, it works. The only problem is on 230V. This could be the 230V heating element, but could also be a failure in the 230V supply. I assume everything else works as it should on 230V?

 

If so, check the 230V supply to the fridge itself (careful! :-)), to be sure the supply is getting right to the heating element. Most fridges share their supply fuse/MCB with a power circuit that powers something else, so you can easily verify that it is not a simple matter of the fuse/MCB having tripped. But a loose connection could still prevent the element heating.

 

There will be a 230V junction box at the rear of the fridge, usually accessible through the upper outside air vent (possibly the lower), where the mains wiring terminates on to the fridge connection cable, I would expect there to be a connection block on the fridge itself (often on the top near the rear) where the connection cable terminates onto the fridge circuitry, and of course both ends of the connections for the heating element. Don't forget to check both supply and return wiring, as a loose/disconnected wire in either will give the same result.

 

As these are mains voltage circuits, if you don't have a mains tester and/or aren't comfortable working with mains voltages, just do visual and physical checks with the mains power disconnected, and leave anything more complex to an electrician to resolve, or do as suggested and contact Dometic under their warranty.

 

Don't motorhomes sold (presumably) in Belgium have to provide a guarantee of the same duration as that provided on the base vehicle? Being Fiat, that should be the standard two years Euro warranty. If so, you could simply return the van to the dealer who sold it, and ask them to sort it out under warranty.

[monique.hubrechtsgm]

Splendid Explanation Brian. And that is exactly what my dealer technican did when looking to him at at the rear open fridge in the bottom area. He did volt readings I/O and decided the resist element was broken. That Ohm resist of that element can also be measured. Hopefully for part and labour free of charge.

[Brian Kirby]

Good. Well done!

[monique.hubrechtsgm]

If interested ican upload a picture of the part changed. It is a cable loom whit a connected angle metal small pipe whit a very strange end. About 0.5 mtr long in total. It can not be removed from the out side. That is only possible if the fridge housing base is loosened and pulled somewhat inboard. About an hour work. However the fridge works again on 230 volt .