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aurgathor
join:2002-12-01
Lynnwood, WA

aurgathor

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refrigerator in a well under 32F room

What would happen in a refrigerator if it was in a very cold room?

Would the inside eventually get nearly as cold as the outside, that is, fall below freezing?

Assume that the fridge is plugged in and there's no power loss, it is in a good working condition, and it is set to 'medium' or whatever's equivalent, like 5 on a 1 to 9 scale.
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ChiTang
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join:2002-08-23
Alhambra, CA

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Re: refrigerator in a well under 32F room

If the frige is well insulated, ambient temp has very little effect on the inside temp, however, if ambient temp is hot, it may have an effect on the working of the frige's compressor, makes it harder to cool the inside.

DracoFelis
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said by aurgathor:

What would happen in a refrigerator if it was in a very cold room?

Would the inside eventually get nearly as cold as the outside, that is, fall below freezing?
Yes. The stuff in the fridge would eventually freeze.

As long as you have a device (a fridge in this case) that can cool but not heat its interior, than there really is nothing else that can happen. Because in that case, the fridge doesn't need to cool down any (and it wouldn't help any if the fridge did try to cool itself more, because you already have all the cooling you need). As a result, the only thing the fridge can do is act as an insulated box. And since no insulation is perfect (although some is better than others), eventually the colder temp will seep in, and cool the interior more than the active cooling unit would have otherwise cooled things.

Of course, if you had a device that not only included a cooling unit, but also had a heating unit (or the ability of the cooling unit to work "in reverse" to heat the interior and cool the exterior) than the situation is different. Because in that case, the unit could sense that the temperatures are "too cold" inside, and start using some electricity to "warm things up" (so they don't freeze). However, I'm not aware of any fridges on the market that have a "heat up the food to keep it from freezing" feature. That doesn't mean they don't exist, but they are likely a specialty item (or worse yet, a custom built item), if you can find them at all.

shdesigns
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Stone Mountain, GA

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Most fridges hav heating. There is a defrost cycle that adds heat.

Many also have heaters in the door to prevent condensation. The heater in mine is broken so there is condensation at times.
mocycler
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The thermostat in the fridge is going to work independently of the outside temperature. Of course, the cooler is is in the room, the less often the compressor has to turn on.

mocycler
CrashD1n3r1
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Canada

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Draco is right, you can't use a simple fridge to keep it at the right temperature. What will happen is simple; the fridge thermostat won't turn on since the interior temp is lower than the required temp to start the compressor. The inside of the fridge will be at the same temperature as the room temp.

wilbilt
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Oroville, CA

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Assuming a typical household refrigerator-freezer...the freezer is normally set to keep the interior well below 32F. The temperature in the refrigerator compartment is some degree warmer than the freezer depending on the setting, but is relative to the freezer temp.

If the unit is in a 30F room, and the freezer is set to 20F, the compressor will run to cool the freezer and pump some heat back into the room. I suppose it is possible the freezer temp could end up cooler than the room and the refrigerator warmer than the room, depending on variables such as time and insulation efficiency.

davidg
Good Bye My Friend
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at work the fridge has always been in the bay. even during the dead of winter the fridge has never cooled down inside enough to freeze anything in teh fridge side. i ain't saying it won't happen, but in our case it never has. the bay might as well be unheated, we only spot heat when working out there.

RockyBB
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join:2005-01-31
Steamboat Springs, CO

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my experience is that ice will build up in the guts of the fridge, which will not effect the contents until the temperature goes above freezing, then that ice will block cold air blowing to the fridge part and eventually the freezer will be freezing and fridge will get no cool air. this is what happened to a fridge we had in the garage last winter. we "repaired" it by removing the contents for two days, disconnecting from electric and opening the doors to let all the ice (that we could not see) melt. no permanent damage. you can verify this by searching on repair tips for refrigerators that don't cool while the freezer works fine -- you'll see guidance not to run the fridge in a cold garage over the wintertime.

james16
join:2001-02-26

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said by shdesigns:

Most fridges hav heating. There is a defrost cycle that adds heat.
While true, those heaters have nothing to do with what is being asked.

A bottle of water in a fridge in a room below freezing will eventually freeze.
boontonflyer
join:2004-07-05
Somerset, NJ

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We have exactly the situation you describe. Household refrigerator in garage (attached to house but unheated). Garage only gets the heat lost from house and the residual heat from single car being returned to garage (once or twice a day). Tends to get close to freezing late night/early morning (especially Dec/Jan/Feb).

Refrigerator works fine. Uneven operating cycle due to colder garage temperature tends to accelerate spoiling of fresh fruits / vegetables in refrigerator section. Don't know if this is actually due to refrigerator getting colder than setting or just uneven cyle affecting relative humidity?

Will have to check inside temp with my IR thermometer on a cold morning. May be able to do it this morning since wind chill is supposed to be 0 deg Fahrenheit overnight.

Paul

aurgathor
join:2002-12-01
Lynnwood, WA

aurgathor

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said by boontonflyer:

Uneven operating cycle due to colder garage temperature tends to accelerate spoiling of fresh fruits / vegetables in refrigerator section. Don't know if this is actually due to refrigerator getting colder than setting or just uneven cyle affecting relative humidity?
Some fruits or vegetables can't tolerate freezing very well, and it will hasten spoilage.

I'll be finding that out pretty soon, too.
Kearnstd
Space Elf
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Mullica Hill, NJ

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if its a must to have a fridge out there i know that they do sell cold climate fridges ment for places like a garage.

ctceo
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South Bend, IN

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If the fridge in question is equipped with 1,1,1,2-Tetrafluoroethane. Worst case scenario is the compressors lubricants become unable to do their job in the cold temperature reducing the efficiency of the compressor, eventually damaging it's components from friction, also may cause motor start up trouble due to insufficient lubrication. There may also be some inefficiency introduced as the gas may begin to liquefy to soon settling in the compressor washing away the lubricant as well.

The lower operating temperatures I've seen recommended for refrigerators is ~50-60 degrees Fahrenheit.

climbers
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Cool! I love thermodynamics...what happens, and how quickly it happens depends on a few things. If the thermostat detects that the temperature in the fridge is higher than it is set for, the fridge will do its normal heat-exchanger thing and slightly warm the room while cooling the inside of the fridge. The temperature outside the fridge will speed this process, if it is below the fridge's temperature. When the fridge shuts off, it just becomes a glorified thermos bottle--no matter what the insulation, and it will reach equilibrium with the room (we used to call this "entropy"). Depending on their relative temps, the room may become slightly warmer, or cooler, but in the end, everything will have the same temperature.

KrK
Heavy Artillery For The Little Guy
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Well, if the air around the fridge was cold, the coils would be able to exchange heat faster, actually making the refrigerator run more efficiently.

heliox
Not at the table Carlos.
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Corona, CA

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This is my rationale exactly why I refuse to live in freezing areas.

I think there is something fundamentally wrong with putting food in the freezer to keep it "warm".

aurgathor
join:2002-12-01
Lynnwood, WA

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said by ctceo:

The lower operating temperatures I've seen recommended for refrigerators is ~50-60 degrees Fahrenheit.
While my fridge is not below freezing, these days my kitchen can get fairly close to it, like 35F a couple of days ago.
aurgathor

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said by climbers:

Cool! I love thermodynamics...what happens, and how quickly it happens depends on a few things. If the thermostat detects that the temperature in the fridge is higher than it is set for, the fridge will do its normal heat-exchanger thing and slightly warm the room while cooling the inside of the fridge. The temperature outside the fridge will speed this process, if it is below the fridge's temperature. When the fridge shuts off, it just becomes a glorified thermos bottle--no matter what the insulation, and it will reach equilibrium with the room (we used to call this "entropy"). Depending on their relative temps, the room may become slightly warmer, or cooler, but in the end, everything will have the same temperature.
You also need to take into account that most fridges also have a freezer section for frozen food, and assuming that the room is warmer than the freezer (which is probably the case for most places where humans live) the compressor will still run to cool the freezer!
megalosaurus
join:2000-11-29
North Salem, NY

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Consider how a typical refrigetator works. There's a single thermostat in the refrigerator section - generally somewhere near the top. When the temperature in the refrigerator gets warm enough, the compressor comes on and starts generating cold. (Yeah - I know, in physics, you don't really generate cold, you only remove heat. But for our purposes, you can think of it as generating cold.) The cooling coils are at the back of the freezer section, so the compressor is actually cooling the freezer, even though the thermostat is in the refrigerator.

You'll see another "thermostat" for the freezer. This isn't really a thermostat. It's a control for a damper that determines how much air from the freezer section gets diverted into the refrigerator. There's a fan near the coils that blows air over them to deliver the cold to the freezer. The lower (cooler) you set the freezer "thermostat", the less of that cold air makes it to the refrigerator. Thus, the compressor has to work longer to cool the refrigerator to its desired temperature. In the process, the freezer gets colder.

If you put the refrigerator in a cold place (temp in the 30s or lower), then the refrigerator thermostat will never trip, and the freezer will never get cooled. Remember, there is no real thermostat for the freezer.

I'm not qualified to speak about the effect on the compressor of operating in a cold environment, but I've been told by multiple AC repairmen that you can trash a central AC unit by operating it on a very cold day. One told me it should have a crankcase heater to guard against that. It sounds reasonable that this warning would apply to refrigerators as well.

The heating elements used in the defrost cycle and around the door might produce enough heat to make the compressor turn on occasionally on all but the coldest days. But the defrost heater has its own thermostat that turns it off when the ice on the coils has melted. Chances are that in a cold place, there would little if any ice on the coils, so the heat would only be on for a few seconds.
Bobcat79
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said by aurgathor:

What would happen in a refrigerator if it was in a very cold room?
The compressor would never turn on.
said by aurgathor:

Would the inside eventually get nearly as cold as the outside, that is, fall below freezing?
Yes.

Now, what would happen if that refrigerator was on a conveyor belt?

God
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Colorado Springs, CO

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as long as the beer stays cold who cares =)
boontonflyer
join:2004-07-05
Somerset, NJ

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Your last statement about the freezer temp still being served even though the refrigerator doesn't need cooling may be the thing that does in the veggies. I checked the temps this mornign (using IR thermometer) and got the following :

Garage (objects) 31-34 deg F.
Refrigerator (outside) ~ 33
Refrigerator (inside) ~ 31
Freezer (inside) ~ 13

Will have to wait for a warmer day and see what the refrigerator (inside) temp is. That should give an indication of the problem.

Paul
boontonflyer

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Think your last comment about the freezer being serviced is the one that causes the final refrigerator temp (in conjunction with the garage temp) to be so cold.

Used my IR Thermometer to measure this AM (outside temp was ~ 15 deg F with wind chill of ~~ -2 deg F).

Garage objects: 31-34 deg F. (depending on mass)
Outside of refrigerator 31-33
Inside of refrigerator 31
Inside of freezer 13

Will have to wait for a warmer day and redo test.

This should shed some factual light on the situation.

Paul
boontonflyer

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Sorry about the duplicate post. Didn't realize it spilled over to the next page.

Paul
Bobcat79
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said by boontonflyer:

Inside of freezer 13
That's warm for a freezer. It should be 0 F or lower.

The problem is that there is no thermostat in the freezer compartment and the compressor only runs as often as necessary to keep the refrigerator in the 30's. One of the reasons you shouldn't have a standard refrigerator in a cold environment. See megalosaurus' description above.
atcole
join:2003-07-21
Chicago, IL

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*** sorry for repeating similar to others' comments... didn't see page 2 comments ********

First off, it's just an insulated box and contents will ultimately freeze if surrounding air is below freezing.

Regarding room warmer than freezer, your conclusion is not so. Most combined freezer/fridge units have only one thermostat that controls a single compressor serving both refrigerator and freezer. The thermostat is set to read temperature in refrigerator; the freezer simply receives a disproportionate (greater) flow of chilled air relative to size of refrigerator, making the freezer compartment colder. The freezer temp adjust knob is usually a simple damper control, directing more or less cold air into compartment, not acting as a thermostat that controls compressor. Under such, when the ambient temperature is at or below the desired refrigerator temperature (32-40 deg), and assuming the internal temperature should be similar temp, the thermostat will not trigger refrigerator to run and therefore no cold air will be pushed into freezer. This most usually causes the freezer to then WARM UP to somewhere near the ambient temperature. If ambient temp is somewhere between 0-40 degrees (i.e. most normal winter days), then your freezer will be UNDER PERFORMING and you should not expect that its contents will be adequately frozen, especially items with higher freezing temperature (sweetened) or with low moisture content (bread). The best place for a spare combined fridge/freezer is in a room heated 50-75 degrees.

Hydraglass
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I live somewhere that gets *MUCH* colder than freezing - as a matter of fact, last night was around 0F and the day today had a high of around 7F. I have a combo refrigerator/freezer in my unheated garage. Stuff in the refrigerator will freeze mighty fast in these conditions - I've made the mistake in the late fall of not taking the beer out of the fridge and moving it inside soon enough. I lost an entire 2-4 of Keith's last fall ('07) as I didn't bring it in and one night in November it was down around -5F at night. A few days later I went out to clean out and shut off the fridge for the winter - and every bottle of beer had broken.

Different models of refrigerators have sensors in different places - some have sensors in both the freezer and refrigerator, others just sense the refrigerator and send proportionately more cooling to the freezer box. In my case I don't know what section the thermostat is in but it most certainly freezes inside the refrigerator box in under 24 hours.

In our climate, the outside "soda/pop/coke (to cover all areas)" vending machines have heat pumps rather than refrigeration units - in the summer they cool, in the winter they "heat" to prevent the contents from freezing on the cold days and nights. I go snowmobile riding in an area that often repeatedly sees -40F/C (same thing) in the winter - and they still have vending machines outside. If you buy a bottle of root beer out of it on one of those days and open it, it steams.
dentman42
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Does anybody know the freezing point of carbonated soda? (Specifically in my garage fridge, I currently have Pepsi, Coke Classic, Cherry Coke, and RC). My garage rarely gets much below 40f but over the weekend I had a reading of 38f. I'm wondering if I've lost several cases of pop...