I have a problem with the heater fan on my Troll 530GT which will only operate at one speed and doesn't sound too good. Three possibilities:variable speed fan switch which is remotely mounted on the side of the wardrobe, the PCB or the fan motor itself.

Does anyone have experience of this type of fault together with a likely solution?

Very grateful for any advice!

Fan running at single speed is a classic symptom of a faulty transistor on the Power Electronics PCB (Truma P/N 40000-60900) which is mounted in the fan housing.
If the fan is running rough it may just need cleaning out or perhaps the motor brushes are worn.

Thanks very much for the info and apologies for not replying sooner; been away from the computer for a week.
There is a listing on Ebay by someone who can repair PCBs for Truma heaters. Might give that a try.