Bosch Serie4 washing machine fault

[mikejp]

I am getting a power trip. Can anyone please tell me what particular stage of the cycle the machine is at (ie is it starting to heat, etc) as it begins the second cold fill? Any information source on the different cycle stages would be appreciated.

[Whitegoodshelp (Andy)]

Hello Mike. Tripping the electrics or blowing the fuses can be very difficult or impossible to troubleshoot without specialist insulation test meter. Most washing machines should start by energising the drain pump for several seconds, then filling up with water for a short time and then draining it out before going on to fill up with water properly and flushing the detergent.

As soon as the drum starts to turn and the water shuts off I would expect most washing machines to energise the heating element. If not it should certainly energise it within the first few minutes. If this is the point that it trips the electrics then the heating element is definitely the number one suspect.

However, the way to test this would be to remove the wires from the heating element and then test with an insulation test meter, which puts 500 V DC through the part to see if any of the current leaks to earth.

Without such a meter you can't check it for low insulation unless by any chance it is a direct short to earth, which as described in my link below may sometimes show up on an ordinary continuity tester. But most low insulation faults will not show up using an ordinary continuity meter.

So the only option then would be to remove the heating element, which can be tricky. It also carries a risk that once removed you will not be able to refit it as described in the other link below. If you can actually see the heating element it may be possible that you can see it has cracked or badly warped. But if not, and it appears to be perfectly okay, that does not mean it is not the cause of the tripping because it could have low insulation inside allowing live electricity to track to the casing which cannot be seen.

 My washing machine is fusing the electrics

How do I remove the heating element from a washing machine?

[mikejp]

Andy - very helpful, thanks. I have further established that even on a 'COLD' wash setting it is tripping, so I do not favour the heater. It appears to be related to water level and a particular water level float switch setting is either causing the trip or something else is tripping during a fill phase. Are the float switches known to occasionally short and are the 'accessible'?

 

The machine completes the 'rinse' cycle without fault involving several 'top-ups'

[Whitegoodshelp (Andy)]

Does it trip if you just put it on a spin only cycle?

[mikejp]

No, only during a fill cycle on a wash programme. Is it safe to assume that the 'COLD' programme does NOT use the heater at all, or is there perhaps a minimal heater application?

[Whitegoodshelp (Andy)]

Okay well that removes the motor as a suspect. Sometimes when a washing machine fuses at the first part of a wash cycle it's when the pressure switch clicks on and the motor starts to run. One thing that would need to be discounted is something leaking and running onto electrics. It's unlikely but theoretically perfectly possible.

Other than that I've not heard of pressure switch causing any tripping of the electrics. When the pressure switch is activated it just passes power to the heating element and the motor.

In answer to your question I believe it is possible for it to still be caused by the heating element. One way to test this would be to disconnect the wires to the heating element (leave the Earth connected) and then very carefully tape them up with insulation tape and make sure that they are not going to touch anything.

If the washing machine no longer trips then this strongly implies it is the heating element though theoretically it's possible that you are taking other wires out of a circuit that could be causing the problem.

[mikejp]

Thanks a lot, Andy - a bit more 'testing' I think. Will look at isolating the heater.

[mikejp]

Pretty certain heater is the culprit. Replacement on order (3-5 working days!!!). Wife demented :-)

[Whitegoodshelp (Andy)]

Thanks for the update Mike. Please let us know how you get on. 

[mikejp]

Will do - found it difficult to get the 'brown' plug off from underneath the beast so left it on and 'de-earthed' instead (yes, I know...). It will be easier to see how to 'unlock' the plug when I take the front panel off.

 

Out of interest, the 'COLD' cycle stopped mid-way and would not progress (but no trip) which caused some puzzlement and makes me think there might, paradoxically, be a heat input at some point in that cycle.

 

'Demented' wife going up and down to the river with stones but coming back for the spin cycle 🙂

Edited February 1, 2022 by mikejp
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[mikejp]

New element (Bosch supplied) arrived. Old one plus 3kg of grotty scale gunk removed and chamber cleaned as best as. Several rinse cycles to rid the scale from the drum but so far washing without tripping!

 

Many thanks for your help.

[Whitegoodshelp (Andy)]

Nice one. 

[mikejp]

In case anyone else has a similar problem, I found this excellent 'espares' video on the task - different model etc but very useful.

 

https://youtu.be/PMYM_j8Uoyk