Truma Ultraheat S3004 only working on 500W setting.

[RapNap]

The title above is slightly misleading:  my heater works fine on gas.   However, when I select the electric heating option on my S3004 heater only the 500W setting supplies heat: if I change to either of the other two settings the relevant lights on the selector switch illuminate but the heat output does not change.   From what I have read elsewhere, this is likely due to failure of the relays on the PCB which I believe is located in the plastic box at the bottom rear of the heater and this, in my case, is below the fan housing, unaccessible unless I remove that housing.   I find I can obtain a relays + transformer kit from Apuljack for £15.90 for me to repair the PCB myself, a complete new PCB from Leisureshop Direct for £124.26.   The issue in either case is accessing the PCB.

1:  is it straightforward to disconnect the hot air ducts from the fan housing and then disconnect and remove the fan housing itself?   If it is,

2:  how do I remove the PCB from that plastic box? And

3: have any of you had experience of Apuljack relay + transformer kits?   I have read that Truma's own relays and transformers are not of the best quality and that it is best to buy better quality non-Truma parts, but does Apuljack's kit fit that bill ?   (The poster who wrote about this years ago on another forum recommended Maplins: I miss them.)

[Labby]

www.arelectronics.co.uk do a repair on these PCB for £50.00 + postage and it could be worth talking to them about what they use for their repairs.