The fault is caused by the drier.
there is a fan in the drier which is a little too big for the housing and it rubs the case of the drier.
This causes the fan to slowdown and overload the circuit.
As the air flow over the heater element is then reduced, it causes the heater to overheat and then it trips out the thermal switch - resulting in F13 fault. I think the fault can also be caused by a build up of lint on the heater element.
The lint can be cleaned out easy, once you get the drier apart.
The fan is a little more tricky. I took the fan out (polished marks on the casing confirm a rubbing fan)and used a chisel to pair off edges the fan blades a little and replaced it (there is a strange type of nut that holds it on)
The thermal switch can be reset very easy, by reseting it with a unfolded paper clip.
In all it took me about half an hour to do and cost nothing in parts and only required fairly standard tools. tools (screwdriver, torx driver, chisel. paperclip) the repair has worked with out any further fault for 3 years now :)
James Webber (Carpenter)
June 2010
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