Hotpoint WDM73 not drying

[medeng1]

After confirming the problem and removing the lid. The 85C thermostat is open circuit. After shorting the stat the dryer is still not heating. Any suggestions would be appreciated

Regards

Andy

[iadom]

Re: Hotpoint WDM73 not drying

85° stat. 😕

There are two stats on top of the heater box, the one nearest the front is the temp control stat, rated at 115°C. The one at the rear is the ‘one shot’ safety stat.

This would obviously have to be rated higher than 115°C or else it would trip before normal operating temperature was reached.

Failure of the drying fan due to broken wiring can lead to the one shot stat going O/C but bypassing that stat ( which is not advisable even for testing ) :rolls: should allow the heater to work.

The wiring harness is clamped tightly to the front of the motor and it is very common for the wiring harness to chafe through here. This will either blow the mains fuse or circuit breaker but sometimes does take out the dryer safety stat. I have seem the wiring cut right through at this point.

Also worth checking were the wiring harness is lashed to the top edge of the cabinet near the motor, it often chafes here as well.

I repair the wiring, reroute and bend the front of the motor bracket back to prevent it happening again.

[medeng1]

Re: Hotpoint WDM73 not drying

Is the drying fan located behind the detergent drawer? If so it is not running although there is 240V present. The motor turns freely and the terminals have 195ohms across them. All the cablling looks OK with no chaffing.

[iadom]

Re: Hotpoint WDM73 not drying

That fan motor should be running during drying cycle. If it is not then that is the reason for the safety stat failure.
The wiring is prone to breaking at the motor connections, and at all of the places along its length where it is secured tightly with the plastic cable ties etc. The fact that there is 240v present doesn’t mean that there is a neutral return. 😉

We do not advocate, in fact we strongly advise against any live testing, there is no need whatsoever to do this. All faults can be traced with a suitable multimeter or megger.

You can gently pull at the wiring at all of the points mentioned to see if there is a break in the wiring inside the plastic insulation.

I’m guessing by your username that you may have a ‘tech’ background, you should check the wiring from the control timer to the fan motor for continuity,its 95{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} certain there is a break somewhere.

[medeng1]

Re: Hotpoint WDM73 not drying

It is definitely the one shot that is open. ( It is the rectangular one at the rear of the two.) Will double check the wiring tomorrow. I understand you don’t advocate live testing but I would like to try connecting this motor directly to mains. If it runs then the wiring is bust. If it doesn’t then the fan motor is bust.

[iadom]

Re: Hotpoint WDM73 not drying

It is very rare indeed for one of these motors to go O/C, occasionally the small capacitor will fail, that can also be checked without going anywhere near the mains power.

The capacitor and the wiring are so simple to test with the correct equipment that it is folly to even bother with the needless attempt to connect it directly to the mains. :rolls:

The capacitor is not available as a spare from Hotpoint now but it should be possible to source one of the correct rating.

[medeng1]

Re: Hotpoint WDM73 not drying

Thanks very much for your help. All up and running again. New capacitor and one shot sorted the problem.

[iadom]

Re: Hotpoint WDM73 not drying

:tup: Thanks for letting us know the outcome. 🙂

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