This Zanussi ZDT41 dishwasher was not heating up. Was it the heating element? My investigation proved in this instance it was not. It was a 13p diode linked to the relay on the control board.
Just changed the heating element and sensor on a Zanussi, but still doesn’t work. Weirdly it works once if left off for a while. Assuming it’s the board now so going to check the stuff you’ve covered here. Thanks for video.
did you find it was the board? i have just had my dishwasher stop heating just as ive lost the boiler during a house extension which is unpleasant timing lol. I am about to rip it apart to go for the element but if you found it was the board i might do that first.
Found your video when searching on faults on a Electrolux ESL 43020 (mine stopped heating water) suspected the control board or relay so watched your video and found the same diode has strange readings compared to the other one on the board ( identical board by the way ). Will order the diodes and see how it goes ..... Cheers
Not sure how changing the back EMF diode would solve this unless it measured short when you took it out, this only comes into circuit during reverse current when the unit is switched off?
I see your point and I don't have an answer for you as electronics are not my forte. All I can say is that subsequently the machine worked as it should as it has done for several others who have posted comments. There is the possibility that it is coincidental, that the process of disassembly "reset" another component, perhaps the relay? Generally relays fail due to either burnt/carbonised contacts or a failure of the windings in the electro-magnet. Hopefully someone else may be able to shed some light on this.
I just wanted to observe that you were misled during your diagnosis, but ended up at the right fix. I have just done exactly the same repair on a different model Zanussi ZDF3014 dishwasher, and all is working OK for me now. That diode is a back EMF suppressor to prevent the reverse voltage generated by the collapsing magnetic field from the relay coil damaging the control circuit. Several years ago I had changed the heater switching relay due to open circuit contacts so I went straight to that to make sure that it was switching OK when I found the faulty diode. The diode is wired directly across the relay coil, in parallel, so the resistance of the relay coil will confuse/mask your readings when taken 'in circuit'. My diode was dead short, so no relay switching. I definitely wanted to check the controller first before getting at the heater buried underneath - and a good job I did!👍
