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I diagnosed a tripped thermostat to the dryer, and replaced this, but it seems that the dryer heater is heating up, getting too hot and then tripping the stat.
The thermistor, element, dryer fan etc all seem fine.
What could be the cause of the heater getting too hot?
I’ve read the threads about the dryer duct modifications, but I can’t understand how after working fine for a few years the problem could be caused by this design issue- I would not expect it to suddenly go, and then keep tripping.
The element getting too hot would indicate an airflow issue, so should I be looking elseware for air blockages to the condenser unit etc? I can’t see anywhere likely to be blocked.
The heater element does not seem faulty (what Ohms should it be?) and the next stop in the circuit is some sort of circuit board – is this possibly faulty?
Cheers
Re: Dryer thermostat tripping – Hotpoint WD865
Lack of airflow will do this. Slow/clagged fan, fluff in the condenser, or the awful little mesh filter fitted to some of these will all trip the safety.
Penguin45.
Re: Dryer thermostat tripping – Hotpoint WD865
The dryer fan itself can come adrift, it becomes loose on the motor shaft and once hot, fouls on the dryer housing.
Jim.
Re: Dryer thermostat tripping – Hotpoint WD865
Thanks
The condenser duct is clear (and no filter) and I’ve cleaned out the pump ‘sump’ too just in case.
The fan motor seems to be spinning OK too.
How would I check to see if water is being pumped into the dryer assembly? I can’t seem to determine if water is going in on the drying cycle before the stat trips. Or would this not matter?
Are there any other things to check?
Although the thermistor seems to work, would this cause the heater to heat up too much?
As a temporary measure while I try to find the problem, Ive reset the stat by poking a thin drill into it. Can this stat be reset like this long term, or do I really need a new one every time it trips.
Cheers
Re: Dryer thermostat tripping – Hotpoint WD865
The safety is designed as a single use device. Repeated resetting will weaken it and cause it to trip more frequently.
Water valves – the coils should meter at c.3.5kOhms if they are working. If they are working, continuity check from the PCB will be required to ensure that the NTC sensor is in circuit. All that’s left after that is the temperature control circuitry on the PCB itself.
Penguin45.
Re: Dryer thermostat tripping – Hotpoint WD865
iadom wrote:The dryer fan itself can come adrift, it becomes loose on the motor shaft and once hot, fouls on the dryer housing.
Jim.
My fan has done exactly that. Once I re fix the fan it will work for a few minutes then work loose. Do I need a new fan or retaining clip or both pls?
Re: Dryer thermostat tripping – Hotpoint WD865
If the fan blade is slipping on the motor shaft,rough up the shaft with emery cloth and apply a little Loctite(other engineering adhesives available)to the shaft and to the fan collett threads.
You should be ok once this has been done.Re: Dryer thermostat tripping – Hotpoint WD865
I’ve checked the fan and water valve and all are OK.
I reset the stat and started the dryer, and the measured the temperature at which it trips, and this was at about 120 degrees C.
So it seems something is not controlling the heater element.
Having checked all the obvious things, I now seem to be at my limit and believe the problem may lie in the electronics.
So do I call out an independent or call out Hotpoint under their warranty?
Hotpoint will only charge labour, so does anyone know how much an independent will charge if this turns out to be a circuit board problem? I presume if faulty, the board will be swapped and not repaired.
Thanks
Re: Dryer thermostat tripping – Hotpoint WD865
kiddo66 wrote:If the fan blade is slipping on the motor shaft,rough up the shaft with emery cloth and apply a little Loctite(other engineering adhesives available)to the shaft and to the fan collett threads.
You should be ok once this has been done.Sorted!
I had a new fan on order anyway. I noticed that the new fan shaft was chamfered whereas the old one (i think), had worn away. On my model there are no collett threads. The fan is held on to the motor shaft by a retainig clip.Many thanks
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