Chest Freezer Converted to Refrigerator

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byQ

Minister of Fire
May 12, 2013
529
Idaho
I've ordered a control unit to be able to use a chest freezer as a refrigerator. Basically it shuts down the cooling motor when the set temperature is reached. Why do this? How much of an energy saver is it?

When you open a normal refrigerator the cold air spills out of it and drops below the warmer outer air it encounters. So the refrigerator has to re-cool the warmer air now inside it. Also chest freezers have more insulation compared to refrigerators.

So when you open the converted chest freezer the cold air stays in place. Additionally, water jugs can be placed in the bottom of the chest freezer to further stabilize the temperature. I've heard the converted chest freezer will use about 1/5 the energy of an average refrigerator.
 
I can understand the theory and agree with it, but in our house a chest refrigerator would lead to some outrageous science project at the bottom of the refer.
 
I can understand the theory and agree with it, but in our house a chest refrigerator would lead to some outrageous science project at the bottom of the refer.

Ya, I didn't think of that the cold air stays but so do all the spills - right to the bottom of freezer/refrigerator. I guess it will need to be cleaned every once in a while.
 
Check out the home brew forums, those guys are are always converting chest freezers to keg coolers with simple PID controllers with great success.
 
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Check out the home brew forums, those guys are are always converting chest freezers to keg coolers with simple PID controllers with great sucess.

I will, thanks for the heads up.
 
You don't need a PID--that's for extremely precise temperature. This controller should fit your needs. Keep the temperature probe in a jar of water. I also recommend having some sort of timer fan to circulate the cool air as well.
 
I've ordered a control unit to be able to use a chest freezer as a refrigerator. Basically it shuts down the cooling motor when the set temperature is reached. Why do this? How much of an energy saver is it?

When you open a normal refrigerator the cold air spills out of it and drops below the warmer outer air it encounters. So the refrigerator has to re-cool the warmer air now inside it. Also chest freezers have more insulation compared to refrigerators.

So when you open the converted chest freezer the cold air stays in place. Additionally, water jugs can be placed in the bottom of the chest freezer to further stabilize the temperature. I've heard the converted chest freezer will use about 1/5 the energy of an average refrigerator.
Great idea. But, may lead to overconsumption of malty beverages while saving energy.
 
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I converted my old chest freezer to a refrigerator years ago. Besides normal issues related to storing and retrieving food, build up of condensation and water dripping to the bottom of the freezer is the main headache.
 
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I converted my old chest freezer to a refrigerator years ago. Besides normal issues related to storing and retrieving food, build up of condensation and water dripping to the bottom of the freezer is the main headache.

How did you do it? What did you use?
 
You don't need a PID--that's for extremely precise temperature. This controller should fit your needs. Keep the temperature probe in a jar of water. I also recommend having some sort of timer fan to circulate the cool air as well.
I use a controller similar to that on my industrial beer fridge (bypassed the old broken thermostat). Works great. I insert the probe into an empty beer bottle to minimize ambient air cycling the compressor when you open the door.
 
How did you do it? What did you use?
I had a used bulb type thermostat that I wired in series with the hot wire to an outlet which serves the freezer plug. I left the freezer thermostat setting at #3 (cold) and the outlet thermostat I set at about 40F, but I used a thermometer in the freezer to get an actual setting that would maintain about 38F in the freezer. The bulb is mounted inside the freezer.

When the bulb thermostat senses a temperature above the set-point, it closes the contact and supplies power to the freezer outlet. The freezer compressor turns "on" and cools the freezer to the point where the bulb thermostat opens the contact and the freezer compressor then is "off." Very simple.

The freezer-refrigerator is a 15 cu ft chest freezer that we replaced with an upright freezer. I tried to sell the chest freezer but got no takers. Thus, the conversion. We use it primarily for beverages and overflow from the kitchen refrigerator. I don't recall how many watts it uses, but as measured with the Kill-O-Watt meter, it was very little.
 
I converted my old chest freezer to a refrigerator years ago. Besides normal issues related to storing and retrieving food, build up of condensation and water dripping to the bottom of the freezer is the main headache.
Us too. Impressive power savings but my wife hated the moisture, the baskets and organizing so she got a 40 year old propane fridge.
We stand prepared to go back to the converted freezer as fridge just in case. For years we ran a 1949 Ben-Hur fridge. Still works but it's like an I Love Lucy thing and small. Was also good on energy but not as good as the converted freezer.
 
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There are some pretty savvy guys over at (broken link removed) can help with this conversion.
 
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It's easy. Buy a Johnson controls A419 unit. Plug it in the wall. Plug the freezer in to it. Toss the temp probe in to the freezer. Follow the button press instructions in the manual and set fridge range temps and you are done.
 
I have 3 chest freezers for my home brew setup. 2 for cold conditioning and serving and a larger one for a fermentation chamber. I use an Ink Bird controller about $40 on amazon .
https://www.amazon.com/dp/B015E2UFGM/?tag=hearthamazon-20
Just saw these the other day - looks like a great option for a number of things around the home/farm! And a third of the price of a A419. How long have you had them hooked up to your freezer/coolers? Is short cycling an issue?
 
I've had these in use for over 3 years , always accurate , never a problem .There are set points to prevent short cycling , high low alarms, very easy to program .