Defrost Heater

After determining that it was the defrost system, I ordered the thermostat. Make sure you look closely. Mine had two thermostats, and so I had to wait a couple of days for the extra part.
1. Remove ice maker if installed.
2. Remove center casing on ceiling and back wall. There may be two screws that need removed.
3. Locate and remove two screws on upper back wall.
4. Remove back wall carefully, revealing coil system.
5. If this was the problem, the coils will be iced over and need thawed. Either time or a hair dryer...
6. The thermostats clip onto the copper tubing, simply pull them off, keeping close attention to the color of the wires.
7. Be very careful touching the bottom of the coils as the defrost conductor coils are along the bottom and encased in easily breakable glass. If you need to replace this as well, remove the center brace (wire)by pulling towards you and then down. remove wire attachments at both ends and rotate coil out of end braces.
8. Replacing thermostats...you must CUT the wires, and attach new thermostats with wire couplers or wire nuts and then wrap with electrical tape that is rated for the cold.
9. Re-attach all parts and replace back wall and coverings.
10. Enjoy!

Tried manually defrosting several times and the unit would work for a couple of weeks and then get frosted over again.
Using this web site I easily found and identified the parts I needed. I ordered both the heating element and the heater thermostat (If I am going to take apart the unit I only want to do it once). Both parts arrived very quickly and were exact replacements for the parts in the unit.
I removed the ice maker by loosening two screws and unplugging the cable. The top part with the light came down by removing two screws. The vent at the back slid up and was removed. The back panel was removed by removing two screws. I could now access the evaporator coil.
The evaporator coil was removed by removing two screws. The old heater element was on the bottom of the evaporator coil and the heater thermostat was on the upper right of the coil.
I disconnected the wire at each end of the heater element. I removed the retaining clip at the bottom center of the coil. The heater element was removed by bending a tab at each end of the element and then sliding it down.
I unclipped the thermostat from the coil and snaked the wires around the coil to the front so I could work on them easier. I cut the thermostat wires, stripped the ends, connected the new thermostat matching the wire colors, soldered both connections and sealed with some liquid electrical tape. I then snaked the wires behind the coil and snapped the thermostat onto the coil.
The heating element slid up into the bottom of the coil and I bent the tabs back into place and reinstalled the retaining clip. I reconnected the wires to the element.
Putting everything back together was a few more minutes.
Total repair time was about 4 hours from starting to empty the freezer to when I turned the unit back on. By far the longest activity was defrosting. The actual repair itself was about half an hour. Emptying, defrosting and cleaning up were the other 3 and a half hours.

No instructions came with new parts. Access to element was impossible until I accidentally discovered that the two styrofoam cushions at the ends of the coils were removable. Once removed, access to the heater and thermostat was very easy.

Unplug appliance, remove freezer shelf, cold air ducts, back of freezer, disconnect light, (My model does not have ice maker. This may also need to be disconnected.)
1.Remove styrofoam cushions at end of coils
2.Locate element between bottom two coils
3.Disconnect the male/female connections
4.Remove support clip under center of element
5.Remove element
6.Replace new element in reverse

Connecting the thermostat wires was challenging because they were somewhat behind the coils.

1.With styrofoam removed, unclip thermostat from coil
2.Carefully cut wires (leave enough to connect new wires)
3.Connect new thermostat wires (color of wires matched on my fridge)
4.Clip new thermostat in place
5.Replace styrofoam
6.Button it all up

With these steps, this job would take maybe 30 minutes; somewhat longer if your model has an icemaker.

Hope this helps.

After several defrost sessions I realized we had a component problem. Freezer and frig would cool up and maintain for a week or so but then the frog would go warm and the freezer would be ice cold. SO it was then I knew it was a defrost sequence matter. Thanks to Parts Select and their part to culprit algorithm it provided me the several most likely parts to be at fault. Since not having a voltage tester it was R/R time so I started with defrost timer and then went on from there. So all in told the bill for parts was around $120 still cheaper than a repair service call and obviously buying a new unit. Replacing the parts was simple, the most difficult being the defrost heater element but nothing to throw your hands up. My advice is just stay patient, do plenty of research and tackle it, you will save hundreds of dollars. Living without a frig for several days can be uncomfortable but I was absolutely determined to salvage the frig and save money and it was all worth it.

First, using a nut driver, I removed icemaker and back panel inside freezer. I unhooked the wire connectors at each end of the heater defrost element and replaced with new element. I reinstalled the back panel and the icemaker.
Second, using the same nut driver I removed the casing located inside fridge on the top. I pulled the casing down & unhooked the wiring harness. I removed the control temp switch which was held in by two clips. I replaced with new switch, plugged harness back in, reinstalled casing and BINGO....it is as good as new....beats buying a new refrigerator anyday!!!!
THANK YOU Bernard S.!!!!!!!!!!!!!!
Sincerely,
Mom of three boys

I noticed that if I unplugged the refrigerator and plugged it back in a while later it would start working but eventually would stop. I deduced the problem was likely the defrost thermostat. I ordered the thermostat but it was in a difficult place behind the evaporator coil which I could not remove. While I was trying to work it into position my hand pressed against the defrost coil and shattered the glass sheath. I ordered the coil and finally managed to get it and the thermostat installed. The refrigerator seems to work fine now.

Thanks to the very fine posts on this site, and availablity of parts, I didn't have to call in a repair man. Due to the near-10 year age of unit, I first ordered a new fridge for the kitchen and moved the GE to the garage. Let it manually defrost. Figured based upon comments posted here I was dealing with the defrost system problem so ordered the temperature sensors for top and botton, the defrost thermostat, and the defrost heater. As a wise poster said, if I am going to pull the damn thing apart, I'm going to make sure I have all three parts in case I need a particular one. Do not have the skill or gauges to troubleshoot electrical components. Parts arrived from Parts Select in great time, and excellent packaging protection. Parts Select also has great diagrams of the unit, although I could not find written repair instructions anywhere. At first I was going to wait for the parts to arrive and replace everything, but since there was a dely in getting the new fridge in, and the freezer section of the old fridge worked fine, once I had defrosted the old fridge, and cleaned up a few of the rusted over connections, I put everything back together, to await new fridge and receipt of parts for old fridge. Well, as is the story of my Karmic life, once fridge defrosted, and I put everything back together, plugged old unit in inside garage, everything came back up working perfectly on the recommended settings for both freezer and fridge sections. Has continued to maintain correct temps for over a week now. Also have new fridge. Don't recommend the top freezer Maytag one for about $700, as construction is cheap, and temps fluctuate all over the place. Had Home Depot exchange out for the LG $740 top freezer model, and am really impressed with its construction and performance so far. (Both units are recommended buys by ConsumerRepots.Org) Not sure how long old unit will keep running correctly, nor what caused it to come back to life after the defrost. Perhaps a simple clogged drain tube, or shorted out rusted electrical connections that I cleaned. Anyway, am keeping Part Select parts on hand for possible future breakdown, and enjoying having both fridges running. We needed additional freezer space, and got the peace of mind of a new unit for the kitchen.

The part i received fit perfect, i just removed the old part and put the new part in with the screw driver.Really easy

diagram from part select matched my fridge perfect. i ordered all parts that involve defrosting coils. ( defrost heater 618, defrost thermostat 620, defrost thermostat 627 ). two wires involved with thermostat, just removed all old parts and replaced with new. Part Select videos helped demonstrate the projects well.