Classixx internal fuse trip

[chrisbeed]

Hi all,

our washing machine (Bosch Classixx) is tripping after starting the cycle at random times. It’s not tripping the power circuit (RCD) it seems to set off a fuse internally. After it turning  itself off it takes a minute or so until the front panel turns on again. At first, it used to turn off half way or more through the cycle but now it stops soon after starting the cycle. I thought it might be related to the drain pump as it seemed to do this when it was time to drain the drum. I suspected the pump gets blocked and the motor runs hot and some internal resettable fuse just trips. I checked for blockages on the in- and outlet but couldn’t find one. Then I turned the impeller of the pump and it didn’t move freely. There was resistance as turning it. I was sure it was the bearings causing the pump to struggle and overheat and therefore trip the fuse but assumed wrong. As I walked out of the post office I opened the parcel with a new pump to see if the impeller turns in the same fashion and sure enough it had the same resistance. I replaced it anyway to be sure and the problem persisted. Now I suspect that there is an electrical problem or something with the thermostat or heating element.

Any hint or suggestion is highly appreciated!

We are running out of clean undies soon.   ;)

Thanks in advance!

Chris

[chrisbeed]

After some research I’m wondering if I should order and replace the mains filter but would be great if someone could back me up on that idea.  I could also bypass the filter to see if it’s fixing the problem but that might not be a good idea as the motor noises from the drum drive and drain pump could harm other electronics.

[Whitegoodshelp (Andy)]

There is normally some resistance on some pump impellers though not too much. I'm not aware of any re-settable internal fuse on a washing machine. Have you checked it in a totally different wall socket? I've seen a lot of faulty wall sockets cause a washer to cut out randomly.

[chrisbeed]

Thanks Andy but I did test it on two different circuits already and my father in law gave me his also broken Samsung 6.5kg top loader machine which has also issues (not draining water) but maintains power in the same power socket. The mains filter doesn’t show any signs of damage (burns, swells...). Maybe there is a fuse on the main board of the machine. I tried to find a schematic but no luck so far. If there is a fuse blowing that usually would mean something is getting too hot (high current draw or even short).

I can hear a relay or solenoid clicking after it turns itself off. Maybe there is a fault with the power control circuitry. It might need a new main board.

 

cheers

[Whitegoodshelp (Andy)]

I've never heard of a re settable TOC controlling the whole of a washing machine. There can be heat controlled TOCs protecting heating elements and motors or pumps but they can't cut power to the whole washing machine. They would just stop the individual part from working. They are also rarely auto resetting and normally designed to trip and stay tripped until replaced. This is because any thermal overload cutout that cuts out when something gets dangerously hot is not meant to keep resetting and then cutting out, resetting then cutting out as this could lead to failure of the device and cause dangerous overheating.

If the whole washing machine goes dead it feels more like the power supply or something wrong with the main pcb or a poor connection on the power circuit somewhere. I had exactly the same thing with my microwave. It was working then just cut out and went dead. It was the neutral wire in the wall socket totally loose. That's why I suggested it as a possibility.

[Jen]

Did you ever figure out the problem because my Bosch Classixx is doing the same.