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What is the highest temperature the fridge should get to if it is set to the coldest setting? I placed a remote thermometer with logging capabilities in the fridge and mine cycles between 32F and 39F when set to the coldest setting which is 9. Should it be going all the way up to 39F?
 

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What is the highest temperature the fridge should get to if it is set to the coldest setting? I placed a remote thermometer with logging capabilities in the fridge and mine cycles between 32F and 39F when set to the coldest setting which is 9. Should it be going all the way up to 39F?

Is it constantly bouncing from 32 to 39 over and over, or is it only getting up to 39 a couple of times per day? I'm thinking it might only be getting that warm during defrost. If so, then that's probably normal, or even a little better than normal.

Even if that's not what's going on, that sounds about perfect. It's really the average temperature that you need to be worried about. As long as your average temperature is between 32 and 39, then you're good.

That means a normally operating fridge could bounce below 32 or above 39 for short periods and still be perfectly ok.

Do keep in mind that if you are trying to narrow the temperature band, it could be hard on the compressor. The narrower the temperature band, the more cycling on and off it has to do. Modern refrigerators aren't known for being able to last a long time to begin with, so like I said, keep that in mind.
 

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I don't think you ever want it at 32 even for a short time, or you could freeze light, low-mass things like lettuce or spinach
It's the product temperature that matters more than the air temperature. Just because the air temperature might reach 32 degrees for a very short time, that doesn't mean that the lettuce will instantly freeze.

The things being cooled are always slightly warmer than the things that are cooling them. For example let's assume that in order to get to an air temperature of 32 degrees the refrigerant that's inside of the evaporator coil might have to start out at 10 degrees. This would get the surface of the evaporator coil around 15 degrees, then the air blowing off of the evaporator coil might be around 25 degrees, and the air temperature near the data logger sensor might be 32 degrees. Then if you were to measure the temperature of the lettuce I might expect it to be around 34 degrees.

At this point the compressor will shut off and everything will start warming up again.

The average air temperature and the average product temperature should be pretty much the same, but the extremes will not be.
 

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I had fun recording things when I bought a data logger a long time ago. Here’s what our fridge did over a 24 hour period. The temperature variance is about 12 degrees Fahrenheit. The fridge temperature setting would have about the mid-point on the dial.

Chris
 

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The freezer section is producing the cold air and a baffle adjusts the amount of air that goes into the refrigerator section. Both sections need to be adjusted. I use a freezer thermometer in the freezer and the fridge sections and check them in the morning.

If a fridge is not full enough too much cool air will spill out whenever someone opens the door and it will be more difficult to maintain the temperature. Even putting in a gallon jug of water will help with this.
 

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I keep my fridge at 7deg's +/- 1 (due to insulin storage)
Freezer at 0 degs'

fridge and freezer will change temp thats ok, only check fridge/freezer in the morning, or after being kept closed for at least 3 hours

freezer will defrost on a cycle, so temp will go up at time (think it's every 16 hours)

What is the highest temperature the fridge should get to if it is set to the coldest setting? I placed a remote thermometer with logging capabilities in the fridge and mine cycles between 32F and 39F when set to the coldest setting which is 9. Should it be going all the way up to 39F?
 

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not sure why a person would need to datalog a fridge, LOL, just keep an eye on a fridge/freezer themometer

as a diabetic, I've kept insulin in my fridge for 15 years and never had a problem, with just looking at a digital themometer :wink2:

LOL to each his own

What is the highest temperature the fridge should get to if it is set to the coldest setting? I placed a remote thermometer with logging capabilities in the fridge and mine cycles between 32F and 39F when set to the coldest setting which is 9. Should it be going all the way up to 39F?
 

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The temperature you log will depend on the location of the sensor. The air stream from the freezer will affect the log temperature swings if care isn't taken to avoid that.

Anything under 40°F. is health code compliant for food but I like drinks down close to 32°F.
 

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not sure why a person would need to datalog a fridge, LOL, just keep an eye on a fridge/freezer themometer

as a diabetic, I've kept insulin in my fridge for 15 years and never had a problem, with just looking at a digital themometer :wink2:

LOL to each his own
Some people, like many on this forum, like to have a deeper understanding of how things work. For example, before I used a logger on my fridge I didn’t realize that the compressor only turns on 4-5 times in a 24 hour period.

Some people keep perishable medicines in their fridge and could benefit from an understanding of how much of the time the conditions are outside the storage temperatures defined by the manufacturer. In this study, that was more than 2.5 hours per day for insulin storage.
https://www.webmd.com/diabetes/news/20181009/home-fridge-may-not-be-best-for-your-insulin

Chris
 

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Instantaneous air temperature isn't as important as the product temperature. The heat transfer between air and the product isn't real fast so the product will usually trail the lowest temperature reading by a couple degrees or so. I always probe some liquid product that's been in the box a while to get a truer idea of the average box temperature.

We always set walk-in coolers for sodas and beer at a cut off temp. of 28°F. air off the coil and cut-on temp of 40°F. to allow for run cycle gravity defrost. The product temp. was usually slightly above 36°F.

On a typical service call on a hot day, I'd select some representative brew and pop it open to check the average box temp... for troubleshooting information you understand. Sometime I'd have to check a couple different ones. You gotta double check data sometimes. :wink2:
 

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I'm on a diabetic forum, and never had anyone ask about really intense questions on insulin storage.

I do know that the best temp is 7 deg's, most newer insulins nowadays are not temp. sensitive, can go up to 30's. Unopened should be fridge stored if unopened.

The vast majority of people are happy to just keep it in a working fridge. Until I started fixing my own fridge, I did not have a clue as to how a fridge works. Having a digital gauge helps me know there is not a problem with my fridge.

I guess the first people twig is when there ice cream turns to water or there lettuce turns solid.

Don't get me wrong, I'm sure there are professional's who need this information, but I doubt your ordinary joe&schmoe dont really care as long as it appears to work.

As I said if it works for you that's cool, I can't understand why that level is needed. There are of course some scenarios but I'm guessing this is a specfic and or professional niche.. cheers

Some people, like many on this forum, like to have a deeper understanding of how things work. For example, before I used a logger on my fridge I didn’t realize that the compressor only turns on 4-5 times in a 24 hour period.

Some people keep perishable medicines in their fridge and could benefit from an understanding of how much of the time the conditions are outside the storage temperatures defined by the manufacturer. In this study, that was more than 2.5 hours per day for insulin storage.
https://www.webmd.com/diabetes/news/20181009/home-fridge-may-not-be-best-for-your-insulin

Chris
 

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Getting the main compartment and the freezer compartment properly balanced often requires trial and error. Also you need to wait a few days between louver or knob adjustments before concluding whether your last adjustment was correct.

The temperature will be more stable, even if the door is opened a little more often then normal, if most of the space inside is occupied with things. Those ice packs that come with Amazon Prime or that steaks by mail outfit are particularly good for a freezer because they freeze at below 32 F. But put in only one at a time if you have several sitting outside to prevent a prolonged rise of freezer temperature as the thing freezes. Gallon jugs filled with plain water can take up unused space in the main compartment.

There should still be some space between food items and between food items and the compartment walls. But ice packs and water jugs may be put right up against the walls that do not contain the cooling coils.
 
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BEST advice EVER :vs_cool::vs_cool::vs_cool:

Getting the main compartment and the freezer compartment properly balanced often requires trial and error. Also you need to wait a few days between louver or knob adjustments before concluding whether your last adjustment was correct.

The temperature will be more stable, even if the door is opened a little more often then normal, if most of the space inside is occupied with things. Those ice packs that come with Amazon Prime or that steaks by mail outfit are particularly good for a freezer because they freeze at below 32 F. But put in only one at a time if you have several sitting outside to prevent a prolonged rise of freezer temperature as the thing freezes. Gallon jugs filled with plain water can take up unused space in the main compartment.

There should still be some space between food items and between food items and the compartment walls. But ice packs and water jugs may be put right up against the walls that do not contain the cooling coils.
 
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