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View Full Version : Will a frost free freezer work in sub-freezing ambient temp?


masterofnone
05-06-2008, 01:48 PM
I'm planning to get a frezer and put it in my unheated shed. It gets to -20F here in the winter. Will a frost free freezer work when the ambient temp is below the freezer temp? Will it burn itself out, or cost me lots of money to run in the winter?

iamthewalrus(:3=
05-06-2008, 02:01 PM
I'm probably admitting my ignorance when I ask this, but: why not just turn it off in the winter?

masterofnone
05-06-2008, 02:06 PM
That would work, but it would require me keeping a good eye on the weather. It isn't uncommon to have 40 degree temperature ranges over the day. I've seen 80F days in January.

Musicat
05-06-2008, 02:27 PM
A standard frost-free unit works by periodically defrosting itself, then draining the water from the inner compartment to an outer area where it is expected to evaporate.

So in your case, under sub-zero external temps, the melting done by quickly and briefly heating the coils to melt the small, recently-formed frost layer, would probably work, but when the water flowed to the outside, it might freeze somewhere in the path. If it froze in the line, it might block all flow and the process would stop or ice would backup inside. If it froze in the evaporation pan, it will still evaporate from an ice state, but the time it takes will be humidity and temperature dependent. It might not evaporate soon enough before the next batch, and the system would suffer.

OTOH, since the evaporation pan is typically near a minor heat source provided by the coils and condenser, if the outside temp wasn't too low, it might work after all. And if your weather is such that it is never below freezing for long, what froze today might thaw tomorrow.

masterofnone
05-06-2008, 02:48 PM
Thanks Musicat, I thought it might be an issue, but didn't know exactly how it worked. I wouldn't want to rely on the coils and condenser providing enough heat, as they probably won't cycle much in the winter. I'd probably be ok with a frost free model, as it's bone dry when it's cold here, but I'll look for a manual defrost model so I don't have to worry about it.

Bill Door
05-06-2008, 03:01 PM
I'm shopping for a freezer for my garage, and ran across something called a Freezerator (http://www.gladiatorgw.com/catalog/product.jsp?parentCategoryId=698&categoryId=699&productId=1707&scr=category&activeCategory=0&activeSubCategory=4) . The large lower compartment is a freezer, and the small upper compartment is convertible to run either as a refrigerator or freezer. The upper compartment even has heaters to keep it from freezing in cold weather if you choose the refrigerator option. It's got a couple of other features to improve performance in a non-climate controlled environment.

I need freezer space, and more refrigerator space would be nice as well, but it's a pretty substantial upcharge from a conventional freezer, and I haven't convinced myself that it's worth the extra money. Not to hijack, but has anyone any experience with one of these?

Rhythmdvl
05-06-2008, 03:08 PM
That would work, but it would require me keeping a good eye on the weather. It isn't uncommon to have 40 degree temperature ranges over the day. I've seen 80F days in January.

In terms of workarounds, why not put a thermostat in line with the power source?

Frylock
05-06-2008, 03:12 PM
If it froze in the evaporation pan, it will still evaporate from an ice state,

Woawoawoawoawoawoawoawoawoawoawoa.

Woa.

Woa.

Ice evaporates?

-FrL-

masterofnone
05-06-2008, 03:23 PM
Ice evaporates?

-FrL-
Strictly speaking, no, but it does sublime.

http://en.wikipedia.org/wiki/Sublimation_%28chemistry%29

Have you ever noticed that old ice cube trays gradually empty?

Frylock
05-06-2008, 03:25 PM
Strictly speaking, no, but it does sublime.

http://en.wikipedia.org/wiki/Sublimation_%28chemistry%29

Have you ever noticed that old ice cube trays gradually empty?

No, but I believe you.

-FrL-

Musicat
05-06-2008, 03:25 PM
Ice evaporates?

-FrL- :rolleyes: OK, nitpicker. Only a physicist would worry about the exact process, but if your ice cubes diminish in size when left in the freezer for long periods of time with nothing but airflow to explain it, nothing prevents the frozen outflow of a frost-free fridge from doing the same thing. Here today, gone tomorrow, evaporation, magic pixies or whatever.

Frylock
05-06-2008, 03:32 PM
:rolleyes: OK, nitpicker.

:confused: :(

-FrL-

Quercus
05-06-2008, 05:03 PM
If the ambient temp is sub-freezing, you're probably not going to get much frost accumulating in the freezer anyway. The manual defrost may not be much of a burden.

But my real advice is to contact a manufacturer of one of the frost-free models and ask them about your question. I'm sure it's come up before, and they'd be the experts...

Musicat
05-06-2008, 05:07 PM
Sorry, Frylock, I just assumed that everyone knows that ice left in a frost-free freezer will "evaporate" over time, and you were being overly pedantic about ice not really evaporating. Maybe you've never observed this phenomena and didn't know it happens?

Frylock
05-06-2008, 05:21 PM
Maybe you've never observed this phenomena and didn't know it happens?

That's right. I'd never heard of this before.

One reason for this might be that I haven't seen ice in an ice tray (in any freezer that belongs to me) in about 12 years.

-FrL-

beowulff
05-06-2008, 05:38 PM
Ice sublimes, just like dry ice does, but not nearly as fast.
(Sublime = solid -> gas w/o solid -> liquid first)

flex727
05-06-2008, 07:49 PM
Ice sublimes, just like dry ice does, but not nearly as fast.
(Sublime = solid -> gas w/o solid -> liquid first)Absolutely it does. Ever seen snow disappear even though it never got above freezing or exposed to the sun?

Mr. Duality
05-06-2008, 10:53 PM
Bought a chest freezer about 4 years ago and installed it in my garage. It stopped working properly in late Fall when the temp in the garage got lower than 40 degrees Fahrenheit. The repairman said the compressor won't work properly in cooler temperatures. I believe I recall something being said about the lubrication in the compressor failing at low temperatures. Moved it inside and it has worked well ever since.

danceswithcats
05-07-2008, 12:15 AM
Bought a chest freezer about 4 years ago and installed it in my garage. It stopped working properly in late Fall when the temp in the garage got lower than 40 degrees Fahrenheit. The repairman said the compressor won't work properly in cooler temperatures. I believe I recall something being said about the lubrication in the compressor failing at low temperatures. Moved it inside and it has worked well ever since.Correct. Heat pumps and other compressor driven devices which have to function in cool climates use a sump heater with thermostat to keep compressor oil sufficiently fluid.

Joey P
05-07-2008, 01:12 AM
I guess Mr Duality mentioned it, but I'll reiterate. It's not the frost free part that's going to be the problem. It's the fact that most compressors won't run when the ambient temp is under 40. Now, when the ambient temp is under freezing this isn't an issue, (well the stuff in your fridge will freeze) the problem is when the ambient temp is between 32 and 40. Not cold enough to keep your food frozen, not warm enough for the freezer to turn on. The result is a melted freezer.

masterofnone
05-07-2008, 09:59 AM
That's odd - We had a big chest freezer in the garage when I was growing up, and I know of at least 3 people with modern freezers in uninsulated sheds, and I've never heard of anyone having a problem with them not working between 32 and 40 until now.

ftg
05-07-2008, 02:04 PM
It depends on the model. There is some oil inside the compressor. If that gets too jelled, bye-bye freezer. You need to check the manufacturer's spec.

As to defrosting, it also varies. My fridge's freezer compartment has an actual heater coil. You can see the orange reflection of the coil in the back when it is running.

Note that defrosting a well maintained freezer shouldn't be that common. I can go years without defrosting my standard freezer. It's kept in a garage and we have quite a humid environment. I keep the door seals clean and we keep the door opening to a minimum.

Here's a link:

http://www.applianceaid.com/garage_fridge.html

Musicat
05-07-2008, 02:12 PM
http://www.applianceaid.com/garage_fridge.htmlA freezer only ( chest or upright ) will often operate fine all year round, but a frost free refrigerator will usually quit during the cold winter months.

<snip>

Under extreme cold/freezing situations, the oil in the compressor could thicken up and cause permanent damage to the compressor. Don't let the garage temperature drop to much below 10 degrees Celsius( 50F ). Otherwise, the oil becomes thick and could cause premature compressor failure.Apparently "cold winter months" means temps in the 50s-60s. Must be a tropical manufacturer/dealer.

masterofnone
05-07-2008, 02:20 PM
In case anyone is interested, I found a site that shows how to add a heater to a freezer to prevent this problem. Apparently it only comes on when the compressor needs to start running and outside temp is <45F.

http://www.fridgedoctor.com/fridge-doctor-book/fitting-a-system-to-operate-in-an-unheated-space.html

Man With a Cat
05-07-2008, 02:45 PM
Like the others have said here. Some manufacturers offer fridge/freezers that are designed to work in cold garages. You pay a premium for them, but they're there.

Mine is primarily a summer beer fridge. In winter when I need beer stored cold in bulk, I just leave it in an open cooler on the garage floor.