Hoover New Wave Plus 5 Washer Dryer - Dryer Will Not Heat

[Curious]

I purchased a Hoover Washer Dryer New Wave Plus 5 1400 rpm, model W2140 back in about 1996. We have subsequently moved to another country where of course the local Hoover service people have never heard of such a machine. So I need help with this problem.

Symptom: All functions operate normally except there is no heating during the dryer cycle. Either on the low heat setting or on normal heat. The "Low heat" diode illuminates when that function is selected. The hot air ducting is an aluminium casting situated along the top of the drum. There is a fan (which operates normally). There are two thermostats which show 0 ohms resistance. The are two other small black square devices screwed to the duct, presumably thermistors. These are both in open circuit state.

The heating element shows about 40 ohms resistance across the terminals. There is no detectable voltage reaching the heating element. The plastic air tube to the pressure valve appears to be clean over its entire length. But I have not been able to detach it from either end to check it. The washing machine spin dries normally.

The unit has a digital display which appears to operate normally during all functions, including the dryer function. All other washing functions operate normally.

What do you suggest for further diagnostics? Your help will be greatly appreciated

[Whitegoodshelp (Andy)]

The two TOC's shouldn't be open circuit. You can safely bypass them temporarily to check that heat is restored. Clearly, leaving them bypassed would be dangerous though.

They shouldn't go open circuit unless it overheated. Overheating is rare on these models. It could be caused by the fan stopping (though not in your case it seems) or a blockage stopping the air from being circulated (this can be checked on your model easily because the door will open as soon as the drum stops turning as long as there is no water in the machine - when you've bypassed the toc's put it on tumble dry and set it at least for 20 minutes (because the first 10 mins are no heat). After a minute, wait for the motor to stop tumbling and while the washing machine is still on - just open the door. You should be able to put your hand to the top of the door gasket to feel warm air being blown down for a second or so)

Finally, check that the cold water is trickling into the condenser chamber. This can be checked by pulling the drain hose out and hooking it over the sink to observe that water keeps getting pumped out every so often on tumble dry.

If everything checks out, and assuming bypassing the toc's gets the heater working then replace the toc's - do not leave them bypassed because they are a safety device against fire caused by overheating!

Buy Hoover TOCs and stats | Washing machine TOCs and stats (other brands)

[Curious]

Thanks for the instructions. Upon bridging the TOCs, there was instant and very high temperature heat - never mind the 10 minutes of cooling - the heat was instant. In fact, within seconds it was too hot by miles to touch. Do you have any hints where I might source TOCs? And what I might expect to pay for them? They are 150 degree © sensors and they carry a number DM150H. They are small black cubes, about 10mmx10mmx10mm with a metal mounting strip which folds up on two sides into the cubes. There are two male bayonet connectors at the top.

Is there a likelihood that the button thermostats may have been damaged by the previous obvious overheating?

(I neglected to inform you in my first message that on my first exploration of the inards of the washer dryer following failure of dryer heat, I found a wire broken off the fan motor, obviously by vibration. I had since reattached it).

[Whitegoodshelp (Andy)]

I wouldn't expect the other stats would be damaged by bypassing the toc's for such a short time. Just put your meter across them to make sure they are still closed circuit.

The wire off the fan motor is very likely to be what caused the toc's to go open circuit. When the dryer fan wire broke, the fan would have stopped running and the washer dryer would quickly overheat. The TOC's (which stands for Thermal Overload Cutout) are a thermal fuse, without them the washer dryer could catch fire if something goes faulty.

The list price for a pair of these TOCs is £8.61. I checked with my supplier but they show no stock. I have other suppliers that I could check though. If they are not stocking them either (which is sometimes the case ie. everyone decides to stop stocking the same slow moving obsolete parts) Then they would need to be specially ordered.

You can either try to source some locally, although I wouldn't be surprised if no one stocks them.

( Related: buy washing machine spares )

[Curious]

Attempting to remove the TOCs resulted in shearing one of the retaining screws. This in turn required drilling the remains out and re-tapping the thread for a slightly larger screw. To do this without depositing metal particles in the manifold, I elected to seperate the two halves of the manifold. That is quite a job. It is a great sealant they use at the factory. Of course, I have none of that sealant so I have carefully put it together again making it fit exactly as it was as far as possible. It does not appear to be leaking. But what is the sealant in case I need to reseal the joint when heat is applied?

[Whitegoodshelp (Andy)]

It's available here high temperature silicon sealant for tumble dryers It's not cheap but there's enough in to seal several housings (which isn't much use when you only need it to seal one)

Anything else would burn under the heat.

( Alternative high temperature sealants )