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Chest freezer to fridge conversion setpoints?

Old_Skewler

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The setup is running with no issues, just can't determine the correct setpoints to program the Temperature Controller.

Anyone with a similar chest-freezer-to-fridge setup could share their setpoints?

Compressor ON / Compressor OFF / Compressor Time Delay?

My current setup is:

- Magic Chef Chest Freezer
- Ecoglow River Pro
- Willhi Digital Temperature Controller
 

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I would think those values are largely your option/choice. Maybe On at 38F, Off at 34F, delay 5 minutes?
 
I think you will find the ones today are highly stratified now that many put cooling coils on bottom instead of top. Temperature is a nebulous thing. Things will be frozen on the bottom and too warm on top. I had to hang a small computer fan that runs all the time and that still doesn't do a very good job. I've lived with them for years and a lot of negatives.
 
If you set the temperatures like DThames suggested, how long are the on and off cycles?

I'm am doing the same thing with a Craigslist 15 cu ft chest freezer. Inkbird temp controller. Contactor. (Don't buy a used freezer, refrigerator off Craigslist. There will be problems.)
 
If you set the temperatures like DThames suggested, how long are the on and off cycles?

I'm am doing the same thing with a Craigslist 15 cu ft chest freezer. Inkbird temp controller. Contactor. (Don't buy a used freezer, refrigerator off Craigslist. There will be problems.)
I just installed an Inkbird controller on my garage freezer... That's a nice little unit for $35

I don't use it for temp control however, I set it to activate a 120 volt light and buzzer alarm if the freezer ever goes above 5 degF.. there's a lot of money in that freezer..

Going to buy 2 more of them for my two other freezers.
 
I think you will find the ones today are highly stratified now that many put cooling coils on bottom instead of top. Temperature is a nebulous thing. Things will be frozen on the bottom and too warm on top. I had to hang a small computer fan that runs all the time and that still doesn't do a very good job. I've lived with them for years and a lot of negatives.
Yeah, I understood from the beginning that this was an affordable solution with limitations, but it is working so far. I hope I'll be able to upgrade the fridge system in a couple of years.

Do you happen to remember the setpoints you used when you had yours? That is something more useful for me to know.
 
If you set the temperatures like DThames suggested, how long are the on and off cycles?
I set the controller for 32F <-> 42F and no time delay.

It does cycle but I don't have enough data yet. Also, I installed a Wattmeter and I want to see how many kWh in a couple of days running.

For less than $250, fridge and controller, and being able to run off a EcoFlow 700 is amazing for me. But eventually I'll start to notice the limitations of this setup. Right now I am happy with it.
 
My setup is a little different. I have a large mass of liquids to "store cold" thru the night. My 7CF only runs in the day and only when the battery is full. That allows me to use only a car battery to power it. I believe my setpoints are 33 and 35F. Morning temp is about 40F. It has a bout a 10 minute delay. Whatever liquid you have on the bottom will freeze. Don't put cans there as they will freeze and split.
 
My setup is a little different. I have a large mass of liquids to "store cold" thru the night. My 7CF only runs in the day and only when the battery is full. That allows me to use only a car battery to power it. I believe my setpoints are 33 and 35F. Morning temp is about 40F. It has a bout a 10 minute delay. Whatever liquid you have on the bottom will freeze. Don't put cans there as they will freeze and split.
This is an interesting solution. Do you have any idea what your average Watt-hour usage is per day? Do you use any sort of fan to avoid temperature stratification?
 
I must use a fan and I don't remember what usage is anymore. Very dependent on how often you put new stuff in like drinks. I can still function with many rainy days in a row.
 
I'm looking into this too. My question is in regards to power consumption. How does a 12v chest fridge compare to a 120 chest freezer conversion as far a power consumption? which is more efficient? I'm planning on a 400 watt solar with 2000 watt inverter such as the blue print on Will Prowse's page.
 
Set mine 34-37F and thats exactly where it stays.No need to set restart delay,its not going to start right back up with the inkbird and its minimum 1 degree temp differential,mine is stock setting whatever that was.They also dont dry things out,a head of lettuce is crisp for around 2 weeks IIRC.My house refer/freezer dang refer temp differential is 32-43 degrees,and freezer is -8 to 17F,wonder why frozen things in it suck?Would add an inkbird to it but like most,has a defrost cycle.

My 120 volt 7cf freezer/refer conversion uses 175w/hrs a day at those settings in 90F ambient temp.I dont know how to beat that.
 
I adjusted the Inkbird delta T using a Kill a watt. Inkbird thermister inside a small plastic bottle filled with 15 degree F freezing point vegetable oil. Every time the lid is opened the compressor doesn't turn on. Plugged the Inkbird into the Kill o watt and each 24 hours, as soon a the compressor turned on, I would zero out the Kill o watt and set the delta T at 40 minus one degree. Next day, write down the usage, zero out the Kill o watt, delta T at 40 minus two degrees. Did the same for five days, increasing the delta T by one degree each day. Ended up with the lowest electricity use at delta T two degrees. Suspect the compressor and the oil like that setting the most.
 
I adjusted the Inkbird delta T using a Kill a watt. Inkbird thermister inside a small plastic bottle filled with 15 degree F freezing point vegetable oil.
That is a great idea.Mine is just in a pill bottle with thermister pushed tightly thru lid and a bunch of holes drilled in it,I like your idea,mine does indeed cycle with opening.Question,Im set to low of zero F,how does the frozen oil work in that regard?What brand oil? As for power usage you are optimizing power vrs optimizing temp? My temps right now are zero,one and one on 3 freezers set 0-3F on inkbirds. Being at zero is AFAIK pretty optimal for food preservation hence my temp settings being priority,nothing wrong at 2F IMO,working great for preservation, correct? What are the temps range in freezer? What are your inkbird settings,I dont understand delta T.Greek to me.
Thanks again,great idea,may steal it LOL

OH,and to add,these inkbirds turn cheapo freezers into finely controlled temp machines,awesome sauce to the nth degree,eh?Inkbirds really up the game!

EDIT-per my wireless thermometers when they hit 2 degrees the inkbirds go on,usually i hit 0 to a rare -1F
 
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