Siemens Wd12D520 Stops Drying

Sorry Ant, it's not forced to be the same cause although it may be and I can understand why you'd assume it was. I try to give general repair advice rather than strip down instructions but I'm not familiar with your model anyway. I can explain how it works so if you can work out what to check from that it will be a help, if not you'd be better not taking things to bits to be honest.

The dryer on a washer dryer is a condenser dryer so water should trickle into a condenser chamber when the steam from drying the laundry is blown as well. The steam hits the trickle of cold water and condenses back into water where it gets pumped down the drain.

If the condenser chamber gets blocked at the bottom it can stop the condensed water running into the pump. If the water stops running into the chamber the steam won't condense and also cause a fault. Likewise if the fan stops running it won't pump the hot air into the chamber and of course if the heater stops working it wont dry them either. Then there are stats and thermal overload cutouts which can go open circuit and stop the heater from working.

Don't touch the machine with it connected to the mains, some of these wires can be live even when the machine is not running.

If it gets hot on dryer and the fan is running then the fault may well be to do with the condenser chamber. Check for the plastic condenser chamber at the back of the machine and make sure there isn't a blockage in the hose leading from the bottom to the bottom of the tub.