I have a ZISS480DMA GE Monogram refrigerator built in 01/02. The defrost cycle is no longer working and ice builds up on the evaporator coils. I want to check the defrost heater, WR51X322, the thermostat, WR50X29776 , and temperature sensor, WR55X10025. I removed the ice maker and shelves, but...
Rick shows you how to get access to the evaporator coil on this model, look at post #6 here:
I have a GE monogram built-in that was built in 2007. Recently it has begun not holding the temperature well. It started with the fridge side running about 46, and the freezer 8 - 10, when they were set at 36 and 0. It seems to run almost continuously in this state, and the temperature slowly...
If its completely frosted up, then you will need a multimer to ohm test which part is bad.
All you do is ohm test the 2 heating element terminal ends and see if you get less than 50 ohms on your meter. If so, the defrost heater is good. Make sure power to the refrigerator is disconnected before accessing and ohm testing those parts.
Jake - I tried to access the coil via the link you provided but my freezer is different. There isn't any access via the freezer when I remove the panel behind the auger. Instead it appears as though the coil is mounted above the freezer inside a galvanized metal box (photo attached). How do I get into it?
UPDATE: I was able to partially access the coil thru the top of the freezer compartment. The styrofoam insulation seems to be glued to the evaporation pan and there are two orange wires on the far side and one green on the near side that I don't think can be disconnected. The coil was free of ice. Thoughts?
Did some more digging and am afraid I'm over my head... I was able to remove the drip pan by disconnecting the two wires and ground. Disconnected the heater - resistance reading was unstable (crud on connections?) but seemed to be around 45 ohms. If so, it's working (consistent with the evaporator coil not being frozen up). Even if the heater was bad (doesn't seem to be the case) I can't see how to get it off the coil from below and can't see how to access from above.
There are a pair of round things (thermostats?) attached to the coil but not sure what they are or how to test.
I'm tempted to put it back together and call someone... though the problem I see in doing so is that there is a hose clamp that attaches the drain pan to a hose that would need to be tightened up and I'm not sure how to do that from below.
If all this was in vain as the coil looked OK, what else could it be? I see that there is a freezer thermostat that is mounted in the fridge side and runs a wire into the freezer. Could this be it?
If I can't figure this out by tomorrow I'll have to call a tech... my wife won't tolerate it any longer!
Tech came out today... problem was embarrassingly simple: the condenser coil was clogged with dust! It looked clean and dust free from the front, but the passages were apparently clogged up (hard to see from the front as they are perpindicular). The tech used a spray bottle to clean them out, and immediately it began working. Symptoms he mentioned that were a giveaway were 1) lots of heat on the right side of the cabinet, 2) not much air flow on the left side, 3) very hot copper pipes, and 4) lots of heat along the left vertical side of the freezer where the copper pipes go down thru the frame. A secondary issue was that the fridge thermostat was likely not working well - he replaced it.
He suggested using the spray bottle technique once or twice a year as a preventative measure.
Live and learn!