Tumble dryer doesn’t heat up
Thermostats & cut-outs how to fit and find the faults.
Common faults –
1 The heating elements can fail (meaning open circuit)
2 There are cut-outs (T.O.C’s) that might need resetting
3 The thermostats (stats) can trip out or burn out (meaning open circuit)
4 Modern tumble dryers also have sensors and pcb’s (Printed circuit boards) these have programs that can fail and circuitry although most should produce an error code showing you were the fault is.
5 Faulty connections and burned wires may also be the fault.
If a tumble dryer that isn’t heating up at all, it needs checking with a continuity test meter. The most common cause is a heating element fails, or a thermostat or t.o.c has gone open circuit. There may be more than just a couple of thermostats some times there is one near the front of the machine inside the casing or by the door vent system.
It depends on which make and model of tumble dryer you have as to how easy it is to replace the relevant parts. Some tumble dryers have heating elements that are easily accessible by removing the back panel, and can be tested for continuity or checked for obvious burning out or open circuit. Others though have their heating elements inside, which aren’t accessible without stripping the dryer down we will try and cover as many as possible in or video tutorials section. Tumble dryer heating elements are always protected by thermal fuses and thermostats which are usually simple devices with 2 wires connected and have a bimetal strip inside them. They can be tested for continuity with a test meter.
The problem is that if a stat (thermostat) or t.o.c. (thermal overload cut-out) has gone open circuit, it may be for a reason. Overheating could have caused it by not being able to vent the air due to a blockage some ware. Blocked filters or even the machine not being allowed its ten minute cooling down period, Overloading can cause it as well. Sometimes they can go for no apparent reason. A blocked or severely kinked vent hose can also cause overheating.
A T.O.C. or thermostat should never be by-passed. They are there to stop serious overheating of the dryer and it could catch fire.
Some tumble dryers like White Knight and some others. Have a reset button on the back which should click when pressed if it has tripped, if this happens more than once there must be something causing it, which needs proper investigation.