Warm Air Heating Fan Not Turning

[colin111]

Hi. I've just bought a house that has an old Johnson & Stanley warm air heating system. Everything seems fine apart from the fact that the fan does not turn when it kicks in. If i leave it for a minute or two the casing of the fan itself gets really hot and there's a definite burning smell comes from it. I've had a quick read up and it appears that it could either be the fan motor or a bad capacitor. If it was a bad capacitor would the motor in the fan still generate heat or is it more likely that the fan motor is done and the whole thing needs replacing?
Thanks.

 

[steadyon]

A bad capacitor will normally make the motor fail to turn and become very hot. The purpose of the capacitor is to create a fake extra phase to get an induction motor going. If the motor doesn't turn, power still flows through the main windings and overheats the motor. If the motor does turn, the heat is dissipated, usually by a built in fan.

 

[colin111]

Thanks for the reply steadyon. I appreciate it can be difficult to diagnose on a forum, but i'm just trying to work out what options to explore before getting an engineer out as the fan itself seems to be a simple enough swap, which would save on trying to find someone with the knowledge and subsequent expense. I will probably try and find a replacement capacitor first and if that doesn't work i'll have to buy a new fan. It's just a short term fix until funds are available to replace system(first time buyer and it's been a bit hard on the pocket).

 

[Rickster123]

You need a local gas safe engineer to take a look. A poorly maintained warm air unit can be extremely dangerous. No diy repair advice on gas appliances is offered on this forum.