Dometic Rm8550

[snailtrail]

My Dometic fridge, RM8550, operates okay using mains electric.

 

 

When using gas, the indicator remains in the ‘green zone’, but the freezer does not freeze, even after 24hrs.

 

 

The temperature dial is set at 1800hrs and I can feel the heat from the exhaust.

 

 

I have changed to using propane gas, since the fridge was last used but was told by the dealer that nothing needed to be changed.

 

The water and air heaters operate okay using propane gas.

 

 

Any ideas of what could be wrong, prior to it being repaired under guarantee?

 

 

Thanks.

 

 

[Lee E]

My Dometic fridge, RM8550, operates okay using mains electric.

 

 

When using gas, the indicator remains in the ‘green zone’, but the freezer does not freeze, even after 24hrs.

 

 

The temperature dial is set at 1800hrs and I can feel the heat from the exhaust.

 

 

I have changed to using propane gas, since the fridge was last used but was told by the dealer that nothing needed to be changed.

 

The water and air heaters operate okay using propane gas.

 

 

Any ideas of what could be wrong, prior to it being repaired under guarantee?

 

 

Thanks.

any funny smells??? Maybe it has lost refrigerant?

[Brecon]

When was the fridge last serviced? and I do not mean just the annual caravan service as that does not include a fridge service, just a check.

[snailtrail]

The caravan was repaired under the guarantee.

 

Apparently it was due to 'moisture somewhere on the outside of the rear of the fridge'.

 

The explanation did not make sense to me.

 

Does anyone have experience of servicing fridges? Can you explain what else, other than the gas burner, should be checked during a service?

[JTQ]

The burner and the flue is the only serviceable bits I know of.

 

What happens where the unit is used on gas is that particles of rust drop down from the flue tube and screw up the proper combustion of the gas. I find its normally during the winter time when the fridge has little use that the rust tends to drop causing problems at the start of the season. Dirty marks from the flue is a sure give-away of burner problems but even without the marks there could still be issues.

With this poor combustion not only is it a relatively "cold" flame but soot soon builds up in the flue and makes the heat transfer even worse hence the unit seems to work poorly on gas.

You can get a special bottle brush to clean out the flue tube; I just use a piece of string and pull a rag through the tube several times. Once this rusting has started it needs cleaning each spring. I used to clean all the burner parts but now find vacuum cleaning up the rust dust works OK so I don't need to break into the gas system.

If you had been running on Butane then this produces much more water vapour in the flame than Propane does, I believe this to be a issue with rusting of the flues.

 

If the ammonia had leaked the unit would not work on electrical heating either, so its not that.

Edited April 26, 2010 by JTQ