Whirlpool WP661566 High Limit Thermostat OEM Part

My Whirlpool dishwasher (wdf520padm3) started leaving food on dishes and not drying dishes as well as it used to, even when I ran the 'high temp' and 'heavy' cleaning options. This started happening after about 3 years of operation. To try to diagnose the issue, I started the diagnostics cycle (see below for instructions on how to do this). However, the 'Clean' LED is also not working on my dishwasher, so I was unable to read the error code after the service cycle finished. I decided to replace both the heating element and the high limit thermostat, both of which I ordered from AppliancePartsPros. I followed the Youtube videos here: https://www.youtube.com/watch?v=xX5-ruvqZaI https://www.youtube.com/watch?v=YfUK6OfTFFc I have 0 experience working on dishwashers, and it took me about an hour to disconnect all the water/drain pipes, electrical, and actually get the dishwasher out of the cabinet.I recommend you take pictures of the electrical wiring before disconnecting so you know exactly how to put it back. Once the dishwasher was out, it was easy to replace the two parts, and getting the dishwasher back in was easier than getting it out now that I knew what to do. I tested the dishwasher afterwards, but was disappointed that the water still didn't seem to be heating enough, and running the sani-rinse option finished with a flashing 'Sanitized' light (meaning the water was not heated to the proper temperature). I found a blog with a report of a similar issue here: https://www.applianceblog.com/mainforums/threads/wdf510paysa-sanitized-light-blinking-at-end-of-cycle.61627/ Requoting below in case the website goes away: "Anytime you replace a part on these new dishwashers you always have to run the SERVICE DIAGNOSTICS CYCLE, and let it run all the way through to reset it back to default. Entry sequence: Press any 3 keys in the sequence 1-2-3, 1-2-3, 1-2-3 with no more than 1 second between key presses. NOTE: Some models have replaced the “Clean” LED with “Completed.” The Service Diagnostics Cycle will start when the door is closed. Invoking Service Diagnostics clears all status and last run information from memory and restores defaults. It also forces the next cycle to be a sensor calibration cycle. LET IT RUN ALL THE WAY THROUGH: Service diagnostic cycle will take about 23 minutes." I ran the service diagnostics cycle, then tried sani-rinse again. Water was heated to the proper temperature (solid 'Sanitized' light now) and everything seems to be working now. Afterwards I tested the continuity of the removed heating element and found that it was faulty, so that was probably the issue.

So, after a lot of digging for my dishwasher I found the heating element and how to change it on this site. I started there. When we reran the dishwasher the same thing was happening... The steam sanitize light was blinking and not completing... Then I found a post about the high limit thermostat. Granted I couldn't find anything on my Maytag dishwasher, only Whirlpool, turns out they are the same, or so my research was telling me. After I ordered this part, we used the video tutorial to try to replace it. Well. we ended up taking the whole dishwasher out and putting it on its side so we could easily see the bottom. The part was not where the tutorial showed - not surprising. So I started calling out the color of the wires I saw on the video so my hubby could find the part. Eventually, we found it was not the part with the blue and red wires connected, we didn't have those color wires, hubby found a blue/red wire and that's when we found the part and followed the video for replacement. After the part was replaced I read something about needing to reset the machine so it would start using that broken part again. Now, I didn't know this when we replaced the heating element, so that might have fixed it, but we never did the reset. After combing sites to find out how to do a reset on my model, we found that we needed to choose any 3 keys on the touchpad and press them in 1-2-3, 1-2-3, 1-2-3 sequence. This started a quick cycle through by the dishwasher software, about 25 minutes, and we loaded the dishwasher up and retested the steam sanitize and LOW AND BEHOLD IT WORKED!!!! Yeah!!! We fixed it. Hope this helps someone else.

After reviewing the other repair stories related to this "7 blinking light" syndrome, I contacted their support staff via Chat. I relayed my symptoms along with model number of dishwasher. She indicated that this would normally mean an issue with either the heating element, the high limit thermostat, or the control board. Since the control board was so expensive and (luckily) out of stock, I ordered only the heating element and the thermostat. After pulling out the dishwasher and removing the existing heating element, I tested it with an ohm meter. It was still testing okay. I was getting the same reading on the old element as the new one that I received. But, since I had the dishwasher all apart, I decided to go ahead and replace the heating element anyway. The dishwasher was over 13 years old, so I figured it was time to replace it. I also ordered the high-limit thermostat since it was relatively inexpensive. Removing the clip that holds this thermostat was a bit more work than I expected. It really took quite a bit of pressure to get that clip dislodged from the panel holding it in place. I finally used a flathead screwdriver to give the extra push on the clip that was needed. We have not experienced the blinking clean light since these repairs were completed. Since I replaced both items, I can't say for sure whether it was the heating element or the thermostat. But, for $100 with shipping, it was a relatively quick and cheap way to get our dishwasher working again.

A neighbor [electronic engineer] aided by the dishwasher's electrical schematic, first changed-out the failsafe fuse with an automatic resettable one. During subsequent dishwashing cycles, the washer turned off-on, off-on, indicating that the High Limit Thermostat or, the motherboard, may be the culprit. The High Limit Thermostat was cheaper than a motherboard. But, the MB may be next if the problem persists. SH

Replaced the High Limit Thermostat