Bosch dishwasher repair - heater didn't work.
Channel: Seth LaForge
Date: 2020-05-21

My ~2012 Bosch SHE68R55UC Evolution 800 dishwasher stopped heating its water a few months ago. The dishes wouldn't get very clean, mid-cycle the water was cool, and at the end of the cycle the dishes would not be steaming hot like they should be.

After an unhelpful technician told me I probably needed a few fill valve, I took the dishwasher apart myself and found the problem: a failed relay to control the heater. It turns out older Bosch dishwashers are notorious for heater relay failures - a trace on the control board overheats and melts the solder attaching the relay to the board:
http://forums.pelicanparts.com/off-topic-discussions/892794-bosch-dishwasher-heater-relay-repair.html

It appears on more modern dishwashers they've solved this problem, but the relay is inadequate and eventually fails due to internal arcing - in my case after about 8 years of use. I replaced my relay with a much larger one, so hopefully the problem will never reoccur.

The original relay was: HF3FD 012-HTF(576) 12VDC coil, 10A 250VAC

Pin-compatible replacement: Omron G5LE-1A-E DC12 12VDC coil, 16A 250VAC
https://www.digikey.com/products/en?keywords=Z2620-ND
This can replace the old relay directly. Hopefully the 16A contact rating will be enough to survive a good long time.

Larger replacement: Panasonic JTN1AS-PA-F-DC12V 12VDC coil, 30A 277VAC
https://www.digikey.com/products/en?keywords=255-1719-ND
This does not replace the old relay directly, but there's enough room in the control board housing to attach the relay to the PCB with double-sticky tape and solder wires from the PCB to the relay terminals. The 30A contact rating should be enough to survive forever.

If you're not up to soldering, a replacement control board is ~$150:
https://partsdr.com/part/00706023-control-board

Here's a video showing how to disassemble the dishwasher - hopefully you don't need to take it apart this much:
https://www.youtube.com/watch?v=AbxxgWf_3pk