WRF535SMBM00 Whirlpool Refrigerator - Overview

Having seen this problem before in other equipment so I had an idea where to look. Problem: the automatic defrost function was not operating. Looking through openings in the back panel of the freezer compartment, you could see the evaporator coils and fins were a solid chuck of ice. There are three logical components to check. Heater element, thermostat (located just above the evaporator) and a relay on the control board (located in the fridge control panel). Checked the heater with an ohm meter -- OK. The thermostat closes the circuit at around 20 degrees and opens at around 32 degrees. Pulled out the thermostat, wiring, fan unit. Everything unplugs, unscrews, and unclips, don't cut wires. Put the whole assembly in a friends freezer for an hour or so to see if the thermostat closes -- OK. Problem had to be with the control board. Replaced control board, reprogrammed it per included instruction. Everything is working again.

Removed the fruit & veggie drawers & the deli (pantry) drawer. Took out the 3 screws, removed the attached parts, put them on the replacement part, reattached it and put the drawers back in.

Here's the part I want to share: PartSelect had a expanded diagram showing the correct part and sufficiently detailed to figure out the repair before the part arrived. That's why I ordered from them. Secondly, I ordered the part Thursday morning--and the thing was sitting on my porch when I came back in from my evening out Saturday--2 days later!!!

The hard part for me was figuring out which part was causing the problem. I read what others had done and followed their test methods. I checked the defroster heater for continuity and the defroster thermostat to make sure it was closing. the defroster termostat has to be cold to check it. You will need to check it while it is in ice or take it out and put it in another freezer for 30 mins and then check it for continuity. Those items checked out ok so it had to be the control board. The control board is a 5 min job to replace but making sure that is your problem is the hard part. I think the control board was bad due to a power surge we had when the power went out and came back on. It might be a good idea to put a surge protector on your home to protect your fridge and all your other electronic stuff. Our refrigerator is now working like new again. Thank you for all your help, Jim