Hi all. I have a real stumper here. Our refrigerator has an intermittent cooling problem. I have read almost all of the threads on this forum and other appliance troubleshooting websites and remain stumped about this issue.
History
Our Frigidaire FRS26R4AB6 stopped cooling properly about 6 months ago. We are in rental house so we made a maintenance call and a repair technician came out and replaced the defrost thermostat. This seemed to fix the problem and we were able to move all of our food back over from the nighbor's - much to their relief! - and it seemed to work fine until recently. I'm not sure if the current issue is related or not.
So, about 2 weeks the fridge again stopped cooling adequately. The symptoms were about the same: first we noticed the ice in the ice maker bin starting to melt and water was running out of it through the ice dispenser or overflowing from that into the bottom of the fridge. Shortly thereafter, the food in the freezer started to dethaw at the same time that the food in the refrigerator started to get warm. One would no longer get that blast of cold air when they would open the door and the milk was a bit too warm for our comfort level. So, we took everything back out again and packed it into the neighbor's freezer again - much to their dismay!
The following afternoon, a repair technician came back out to look at the unit. He looked around inside and took off the cover to the evaporator coil. After looking at the coil, he said that the coil was bad because the bottom two runs did not have any ice on them. I am not sure how long ago the defrost cycle had completed. He said the cost would be about 800 dollars and we would be better off replacing the unit. I was not really convinced by this diagnosis, but they seemed fine with the idea of replacing it so I let it go...
So we could have some level of refrigeration while we waited for the new unit, we cranked the unit to max and put about 40% of the food back in the refrigerator and about 10% back in the freezer. After we did so the refrigerator cooled fine. Everything was cold and the stuff in the freezer was frozen solid. We did not run the ice maker during that time.
About a week later, our rental company sent us a brand new fridge that was about half the cubic footage, was a top-bottom unit, had no ice maker, and was only about half the width of the space for it. Pretty much a college dorm fridge. My wife freaked out and made them take it away. She called them back and said they needed to replace it with something that was "substantially similar". They refused. So, we decided to try to fix it ourselves. I called a small mom and pop repair company who said if it was the coil, they could do the whole job for 200 bucks. We were thrilled so asked them to come out. He poked around in there and discovered that the defrost thermostat was not clipped on to the refrigerant tube and was just sitting in the bottom of the compartment. It's clip was nowhere to be found. He replaced it with a new one and said that he did not think the issue was a problem with the sealed system. He said the thermostat may not fix it but to monitor it for 24 hours and call him back. We put the cold controls back to factory settings, turned the ice maker back on and monitored it for the next 24 hours. It was making cold solid ice. We also put thermometers in the freezer and fridge and monitored the temperatures. They consistently stayed within the safe limits - 0 to 5 for the freezer and 34 - 40 for the fridge. After 24 hours, we brought all of our food back from the neighbor's - I think we could actually hear them cheering for joy as we drove off! - and put it back in the fridge. The fridge and freezer were both pretty full now. Within 24 hours, however, everything started to dethaw again. Ice melted, freezer food dethawed, milk got warm again. Freezer temps at 20, fridge at 45+. That evening: everything back to the neighbors - this time we just snuck into their garage at night and put it in there without them knowing!! That same night, we would hear a loud buzzing noise that sounded like the compressor trying to start up. We had heard this a few times previously when the unit was full of food, not not nearly as frequently and only intermittently. It would do this about every 5 minutes. I listened to it for about an hour before going to sleep. The next morning, that noise had stopped and the fridge was cooling properly again.
Called the mom and pop repair guy back. He said he knew that the problem was the adaptive defrost timer board. He was convinced of it and told us to order one and he would come back and put it in. Wife was not convinced and neither was I.
We had taken about 60% of the food from the fridge and 90% from the freezer, and she was working fine. The following weekend, I did some troubleshooting of my own to try to narrow down the issue.
What I Have Tried
1. First, checked the evaporator coils inside the unit. The bottom two coils again were not frosted.
2. I pulled the unit out and thoroughly cleaned the condenser coils with a leaf blower and Kirby vacuum cleaner. They were filthy and spread dust bunnies all over the kitchen, much to my wife's dismay.
3. Checked the coils about an hour later and most of them are frosted except for about a 2" section on the very bottom run.
4. Triggered the defrost cycle by pressing the door switch 5 times in 6 seconds. Defrost cycle kicked on. Compressor turned off. Evaporator heater came on. About 20 minutes later, defrost cycle turned off. When the compressor tried to kick back on, it made the loud buzzing noise we had heard the night after emptying the unit for the last time.
5. Went behind the fridge and listened. I could hear a loud buzzing noise for about 3 - 5 seconds followed by a click. Compressor would not turn on. About 5 minutes later, I would hear another click and then after 10 more seconds, the buzzing would start again. This cycle repeated about 5 times and then finally the compressor started up without a problem.
6. I was able to get the sequence in 5 to repeat again by allowing the fridge to run for 30 minutes or so and then triggering the defrost cycle again.
7. I unplugged the fridge for about 30 minutes and then plugged it back in. The compressor fired up without an issue.
8. After plugging it back in, the unit went into defrost about 3 hours later and completely dethawed the coils. After coming out of defrost, the compressor fired up fine. There was some buzzing at initial startup, but it fired right up and the buzzing died down after about 3 seconds. I will monitor it to see when the next defrost cycle kicks in.
I don't want to influence any opinions, but I have narrowed it down to 5 possibles:
-Compressor
-Refrigerant leak somewhere
-Compressor start relay
-Compressor run capacitor
-Adaptive Defrost Controller keeping defrost heater on too long or starting defrost too frequently
That's a pretty broad list!
The thing that stumps me here is the fact that the unit works fine when only partially loaded with food but poorly when full.
I apologize for the long-winded type-up. I did not expect it to be so long but I wanted to provide thorough information to best help inform opinions. Any help anyone can offer would be much appreciated. I will, in return, follow up with the outcome and describe the fix, if any, in hopes that it may help others with a similar problem who may stumble upon this thread.
