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Old 01-11-2010, 03:15 AM   #1
Pash91
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Dec 2009
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Hello,
I finally got around to doing work on my Keezer today. I installed the Johnson controller and noticed something interesting. The deep freezer was getting really hot on the sides. It got to the point where at one point it was almost burning. I set the controller to turn the freezer off when it got to 26 F; however, I noticed that the freezer is dropping to 21 and not turning off. I also set the freezer to its lowest setting. I'm afraid of leaving it on overnight for fear of the compressor exploding, or worse. Are there any settings I'm missing on it?

Thanks!

 
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Old 01-11-2010, 03:18 AM   #2
Pash91
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Also, the temperature alarm is going off saying that the fridge isn't cold enough inside, which is false

 
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Old 01-11-2010, 03:19 AM   #3
remilard
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Quote:
Originally Posted by Pash91 View Post
Hello,
I finally got around to doing work on my Keezer today. I installed the Johnson controller and noticed something interesting. The deep freezer was getting really hot on the sides. It got to the point where at one point it was almost burning. I set the controller to turn the freezer off when it got to 26 F; however, I noticed that the freezer is dropping to 21 and not turning off. I also set the freezer to its lowest setting. I'm afraid of leaving it on overnight for fear of the compressor exploding, or worse. Are there any settings I'm missing on it?

Thanks!
Do you have it in cooling mode?

 
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Old 01-11-2010, 03:26 AM   #4
Pash91
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I haven't opened it up, but from what I can tell it is. It has the snow flake on the display

 
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Old 01-11-2010, 03:48 AM   #5
Pash91
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Actually, I unplugged the controller and plugged the fridge in directly. The temperature light is still blinking and the sides are heating up again

 
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Old 01-11-2010, 04:02 AM   #6
Catt22
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The condenser coils are located in the outer walls of the freezer. They will radiate heat. This is completely normal. The evaporator coils are also located in the freezer walls, but they are up against the inside walls. The two are separated by foam insulation.

The snow flake on the display indicates that the controller is in the cooling mode, so that's OK. That is normally the default setting. The controller default setting should also start the compressor at the Set Point (Cut IN) and it will stay on until it cools to the Set Point minus the Differential setting. IOW, when you set the controller to 26 it will keep running until its gets to the Setpoint temp minus the Differential setting. What do you have the Differential set to? It can be set anywhere from 1 to 30 deg in either F or C.

No need to fear the compressor exploding. It's designed to run for extended periods without issues. I suspect you have the differential set incorrectly and too large. Typically somewhere between 3 and 5 degrees works well. I use a 5 degree Differential.

The freezer alarm will probably keep going off unless the freezer gets to normal sub zero temps which it never will the way that we use them. You may need to figure out a way to disable the alarm somehow. Mine has no alarm, so I can't help you there. You do want the freezer to be set at it's lowest setting. Essentially, this takes it out of the loop and turns over the control to the Johnson.

I'm pretty sure it's a problem with the Differential setting. Check that first.

 
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Old 01-11-2010, 04:06 AM   #7
Pash91
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I actually didn't change the differential. It's set to 5 right now. Everything else is set to default. Is there a way to tell it to cut off the second it hits the set point, that is, from what I understand, if the set point gets hit and the fridge cuts off, then the temperature rises and dips really quickly, the controller won't catch it. I want it to react immediately no matter what

 
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Old 01-11-2010, 04:06 AM   #8
Pash91
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I'm really worried about the sides heating up. I think they could actually burn skin at some points. That doesn't seem normal to me

 
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Old 01-11-2010, 04:11 AM   #9
Catt22
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Quote:
Originally Posted by Pash91 View Post
I'm really worried about the sides heating up. I think they could actually burn skin at some points. That doesn't seem normal to me
It's completely normal. They will be less warm once you get everything cooled down and the compressor begins to cycle. The heat you feel is what is being removed from the interior of the freezer.

Did you check the Differential setting?

One thing you can do is establish the Set Point relatively high initially, then adjust it downward gradually over the next day or so. This will reassure you that the compressor is cycling properly. Set it at 45 F and see if it shuts off. Then go down from there as desired.

 
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Old 01-11-2010, 04:17 AM   #10
Pash91
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Yes, I checked the differential, it's set to 5.

My problem is that, once it cools, it's fine, when it's working. It was dropping to 21 and not cutting off even though my set point is 26. Should I drop the differential to 2?

 
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