G.E. GTH22SBRARBS Top Mount Refer

[generaltech1]

Ok I get a call that this refer isn't cooling, but when I get there, of course its cooling.  Temps looked good, amp draw off the compressor good. They tell me that it will work fine for a while, then melt the ice, then refreezes it into a block in the bucket.  Dont have a service manual or schematic, but I suspect the motherboard, just as an educated guess. Any help would be great, thanks!

Model GTH22SBRARBS

[JWWebster]

This ice box has auto defrost. It uses sensors to determine defrost instead of a timer. When defrost has been determined by the board from various inputs, the icebox goes into a pre defrost by doing a chill down to insure that when the defrost occurs the food won't melt. So with the food super chilled the thang then goes into defrost. If them sensors is whack the thang won't act right. keep in mind it still uses a termination thermostat and a conventional heater to do the defrost HOWEVER the defrost time varies this is known as DWELL mode any where from 20 to 40 minutes. After that a post dwell period begins where the compressor is fired up by the board but the inside fans remain off to speed up the cooling process. All of this is monitored by inputs on the mutha board. Those inputs is from sensors placed aboard the machine to monitor the ice box. Ryan has more here:

[jesse24]

 Something I have found with these GE boards is the compressor relay solder joint is cracked which can cause intermittent cooling. look close at the joint, you may only see a faint dark ring in the joint but that all it needs to not pass current.

[niobrara]

Check the rubber gaskets on the sides of the evap, if rippled and yellow colored heater is sticking on. If not check thermistors, if in range replace control board.

[AJ]

Here is the one for your model refrigerator.

Seems to be a popular part for GE refrigerators.

GE Main Control Board Assembly, part number: AP4436216

[generaltech1]

So I was correct, I need the motherboard?

[AJ]

Check the rubber gaskets on the sides of the evap, if rippled and yellow colored heater is sticking on. If not check thermistors, if in range replace control board.

[generaltech1]

What should I read off the thermistors if theyre bad?

[JWWebster]

[ApplianceGuru]

Bad solder joints on a board are often the result of a bad board component drawing too much current and/or generating too much heat.  This heats and re-heats the joint, causing it to crack.

It is best to replace a board if you see cracked solder joints.  I tried solder them for the first year or so.  Then I started getting callbacks for the exact same thing.  Lo and behold, the solder was cracked again!!  Not to mention, many boards were burn beyond a solder repair.

[generaltech1]

Ok heres what I got from testing the thermistors, Freezer:16.5k ohms, FF: 15.1k ohms, and Evap: 12.2k ohms.  So going by the video in the the thread, I have 2 out of three thermistors bad since they all dont read 16.5k ohms +/- 5%, correct?

[Brent@CanBC]

    Hey my friend, hows things going.   So yes to changing out the two thermisters that are out of the +/- 5%  and that should fix your problem.  Much cheaper than guessing and finding the board is not the problem.  Brent@CanBC

[JWWebster]

The themistors also need to be correctly mounted.

[generaltech1]

Compressor amp draw is 0.9 does that sound right?

[niobrara]

yes