[Gene]

Originally Posted by lancer

...So if I can (hear the nosie) the problem is the defrost timer? It seems to me it's the other way around (if I can not hear the noise then the problem is the defrost timer)...

Dan,

The defrost timer is just a switch, operated by a motor. There are two pairs of contacts, one of them provides power to the compressor and another one - to the heating circuit.

If the motor is bad, it's causing the compressor contacts to get stuck, then it will never switch to the defrost cycle. When you manually turn the shaft that means you manually switched the defrost "on", and sizzling sound proves that the defrost circuit is fine. In your case it looks like the defrost pair of contacts in the defrost timer is bad and the correction is to replace the defrost timer. Also I would recommend to check wires to the defrost timer.

- The part number for the defrost timer is AP98191

Gene.
P.S. You can check the defrost timer for continuity according to the Wiring diagram.

[mhf115]

Gene,

Thanks for all the good info thus far: here is my situation.

Frigidaire Top Freezer model.

I had the ice build up on the coils in my freezer compartment. I manually defrosted everything (hairdryer) and put everything back together. Same problem arose in about 2 weeks with a warm fridge compartment. (more ice on the coils).

I am looking at the three parts (heater element, defrost timer, and thermostat). I ohm tested the heater element and got infinity (switching the probes around if that mattered).

I did not run any ohm tests on the thermostat as I am not sure where to connect the probes to (should I cut and strip the wire and then reconnect?

Here's the kicker; my defrost timer is one of the electronic ones you mentioned. I read somewhere that on my model (frigidaire FRT21H7ASB2) you need to toggle the light switch 5 times within 7 seconds and it should manually put the refrigerator into defrost mode. It does not do this and continues to run when I toggle the light switch.

The fridge does actually shut off occasionally (is this defrost mode? if so is the timer ok?) If it is defrost mode, I am looking for a glow from my heating element when the fridge is off, but there is no glow, the heating element is not turning on (obviously because of my problem).

This would lead me to believe the thermostat needs to be replaced; however, not being able to manually put my fridge into defrost mode has me concerned it might be the electronic timer. Everything else seems to point to the fact that the timer is working. If you could give me any advice as to which parts to order or further tests to run, I would greatly appreciate it.

Thanks so much.

Mark

[Gene]

Originally Posted by mhf115

...I ohm tested the heater element and got infinity (switching the probes around if that mattered)...

Hi Mark.

The defrost heater is bad. No doubts about it. I would recommend to replace the defrost thermostat too because the part is inexpensive and will make the repair more reliable.

- The part number for the defrost heater is AP2150162

- The part number for the defrost thermostat is AP2150133

Gene.

[Charlene De La O]

Hi,

I have a Kenmore refrigerator/freezer, model 106.70192000. It is eight years old.

My problem seems to be related to this thread. There was water in my refrigerator, so I read some posts and fixed it by clearning the drain hose from the freezer. It turned out to have a chunk of ice in the hose. There was also a ton of ice all over the bottom of the freezer, which I cleaned out, melted, and dried. I even left my refrigerator and freezer open and turned off for 72 hours to make sure that everything was melted and dry.

Now the problem has returned. A lot of ice has formed on the bottom of the freezer (under the plastic pan that I removed). It leaks into the refrigerator and forms puddles of water and sections of ice on the shelves. When they fill with water and ice, it runs to the bottom of the fridge, some more ice forms there and eventually water runs out of the bottom of the door and onto the floor.

It seems clear that whatever caused the drain to plug with ice in the first place is still a problem. So, I figure it could be the defrost system. I am starting with Greg's troubleshootings steps. I found the defrost timer; it looks just like the part number AP3110896, shown in this site's pics. But I can't locate a "shaft in the middle" that I can turn with a screwdriver. It's all encased in clear plastic and even under that I don't see any shaft to adjust.

Also, does the fact I can see the parts moving under the clear plastic an indicator that this part is working?

Thanks for any help!

Charlene

[mhf115]

Gene - Thank you. I will replace parts and update.

[Gene]

Hi Charlene,

Before replacing any parts I would recommend to remove the rear cover and clean the condenser coil and all around from lint. Be sure the bottom end of the drain hose is open.

Gene.

[DaveR]

Thank you Gene, it now makes sense.

[mhf115]

Gene-

I diagnosed my problem inproperly to you. My heater element read that I had a closed circuit. On my ohmeter, my bar went to the far right which I thought was infinity. I had the same reading on the new heater element.

So I have a closed circuit with my heater element that is already in the freezer. I took out the defrost thermostat and I checked for continuity. It was closed when cold and open when warm. I ended up replacing that piece anyway.

So where I am now is I have my new defrost thermostat in (the old one should have been good). The old heater element in (also tests good "i believe").

My options now are to replace the heater element or the electric defrost timer. What is your opinion on where to proceed? If you recall, I could not manually put my fridge into defrost mode by toggling the light switch. The fridge was also shutting off periodically. Let me know how I should proceed.

Thank you.

Mark

[Gene]

Hi Mark,

If there is nothing wrong with the defrost heater and the defrost thermostat then the problem is a bad adaptive defrost control. No doubts about it.

- The part number for the adaptive defrost control is AP3211551

Gene.

[mhf115]

Gene,

Thank you - I ordered that part and last time the shipping was very fast. I will update once installed. I know this is not your department, but should I be able to return that defrost heater element that I did not install?

Thanks again,
Mark