Repeat repairs including sealed system repairs on sub zero freezer

[Ned.B]

This isn't a DIY repair, but this seems to be the best place to put this. Looking for some professional second opinions on what else we can be doing here.

We have a set of subzero 501 built in refrigerator and freezer. Even though they are from 1987, the appliance technitian we initially had come look at another appliance has from the beginning said that he would never replace them. Any part that was needed work he could get.

We initially had the tech come back to look at the refrigerator side. The refrigerator was having by freezing and condensation problems and the hose to the drip pan was clogged. This was fixed by adding a second thermometer to balance the interior temperatures and replacing one of the heater units underneath to keep the hose to the drip pan from freezing.

At the same time we asked why our freezer was forming ice in the bottom of all of the drawers (but otherwise working as it should). The answer was that both defrost heaters had stopped working. Those were replaced and the problem with the ice appeared to be fixed.

Since then we've had ongoing problems.

A few weeks later we noticed the freezer temperature increasing rapidly. He was back out that night and replaced the compressor switch assuming it had been ready to break, and just happened to fail after the last repair. A month later we returned home from vacation to a room temperature freezer with rotting food. The diagnosis was the compressor had failed and it was replaced. Since we were offered a deal, we decided to go ahead with the ice maker install that we had wanted for some time. While he was back two weeks later to install that the tech noticed it still wasn’t getting down below 7 or 8 degrees. He balanced the refrigerant levels and replaced the switches on the door having determined that they weren’t functioning and the fan was not turning on when the door closed. A previous owner had replaced them with the wrong part.

Now a month after this the we noticed our food was starting to thaw. We checked the temperature and it was only maintaining refrigerator temperatures. It stayed at 40 all evening. This morning it was 50 and climbing fast. When it was starting to heat the interior and was reaching 80 I turned it off. So what gives? We’ve touched many major component of this unit and it’s still having problems. We are calling in another repair this morning but I wanted to see if anyone else had any thoughts.

[LearningTech]

Im impartial, but distant 3rd party but i cant tell everythig going on

they can. Just be bad when they are that old, and can have all the issues you have had naturally. It is good to repair those units cause at. A repalcemet cost of like 7-15K you can do a LOT of repairs. 

However A few red flags.

On 3/5/2020 at 7:36 AM, Ned.B said:

was fixed by adding a second thermometer

This is extreamly odd. You dont just add a second control. You repair/repalce  the one that is there. 

 

On 3/5/2020 at 7:36 AM, Ned.B said:

The answer was that both defrost heaters had stopped working

If ice is forming at the bottom ( like a ice sheet) that means something had melted frost to make water to make ice. Heaters would be one of the last things i would check.  Frost on bottom of drawer is a different story. 

 A bad heater would cause low/no cooling. Also heaters like never break in pairs. It may be best to repalce in pairs, or thats how they come, but they dont fail in pairs. 

On 3/5/2020 at 7:36 AM, Ned.B said:

assuming it had been ready to break

Makes no sense to do that. Unlss there was something that tested bad on it. But for the most part they test good then test bad. Very little mid ground. 

[LearningTech]

On 3/5/2020 at 7:36 AM, Ned.B said:

fan was not turning on when the door closed.

Should check that long befoer repaleing compressor

[LearningTech]

On 3/5/2020 at 7:36 AM, Ned.B said:

as reaching 80

Can be natural. Bad control or a short. Check to make sure eaters are not shorted