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How long does a freezer stay frozen when the power goes out?

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Re: How long does a freezer stay frozen when the power goes out?

#171

Post by dawnerd »

Mathnerd314 wrote: post #31
pengaru wrote: post #18

A test with the freezer as full as possible with just water would be interesting as a best-case set of data points to compare against. I always keep containers full of water in the bowels of my refrigerators/freezers only removing them when the space is required for food. There's not much sense in keeping empty volumes of air in a refrigerated space.

When there's no airflow in the refrigerator, then it takes a long time to chill food, the reverse of how a blast chiller can chill food really quickly by moving lots of air. But maybe the water chills the air to make up for this, IDK. It would be interesting to experiment.

I can say that if I load up my fridge, especially the top it will freeze up the fan and stop working altogether. Airflow is essential if you have a poorly designed Samsung where it’s a common problem to ice over.

Re: How long does a freezer stay frozen when the power goes out?

#172

Post by nikau »

sjwright wrote: post #165
nikau wrote: post #152

Earlier quoted context omitted.

> My venture custom designed and built a refrigeration circuit with autonomous electronic management Is that a web 2.0 way of saying a thermostat?

It's probably a web 3.0/IoT way of saying an ESP8266 with a couple of sensors and a relay. From there you could do some slightly smart stuff like observe the rate of warming towards ambient when idle (i.e. determine the volume of material in the freezer) to determine how long you can go without running the compressor. And from there you could manipulate the thermostat's target depending on current and future predicte…

Yes, given the thermal mass of a fridge any type of advanced control is probably pointless.

I think late 90s/early 2000s was the peak of fridge reliability to efficiency ratio.

They run the defrost timer through the thermostat, so defrost cycles are somewhat inline with fridge use.

The circuitry is simple - a defrost timer, PTC "relay", a few thermostats and the compressor.

Newer fridges are a bit quieter and more efficient with inverter technology, but failure rates are way higher due to electronics failures.

Re: How long does a freezer stay frozen when the power goes out?

#173

Post by distances »

chopin wrote: post #144
BrandoElFollito wrote: post #134

Earlier quoted context omitted.

I used gas for 20 years, then induction for 10. Induction wins everywhere (reproducibility of heat, speed to heat, ease of cleaning...) The only thing I miss a tiny bit from gas is the ability to tilt a pan to have oil gather in a puddle to deep fry something small. Other than that everytime I use gas I long for induction.

+1 for induction. Gas heats up the handles pretty fast, too.

And not only handles, on a summer day the kitchen can become warm pretty fast when cooking with gas. Assuming no AC of course.

Re: How long does a freezer stay frozen when the power goes out?

#174

Post by distances »

drevil-v2 wrote: post #130
morninglight wrote: post #64

The location of the freezer or refrigerator is critical. If you live in a house that has a typical unfinished basement, don't overlook the advantage it offers. With one simple change, you can noticeably lower your electric bill, reduce your carbon footprint, gain extra kitchen space and improve your health. Just move your refrigerator to the basement. Since the basement is normally cooler than the upstairs, the refri…

What about the calories used to travel up and down the stairs by multiple family members? Say over a month you burn enough calories to eat an extra steak to make up the energy lost, would the environment be better or worse off? What about time lost? Say you wasted an extra hour or two every fortnight just getting to and from the fridge, what if instead you had read a book or worked on your hobbies? Would you be happi…

Would you use the same reasoning against exercising?

Re: How long does a freezer stay frozen when the power goes out?

#175

Post by mschuster91 »

jve wrote: post #131
morninglight wrote: post #64

The location of the freezer or refrigerator is critical. If you live in a house that has a typical unfinished basement, don't overlook the advantage it offers. With one simple change, you can noticeably lower your electric bill, reduce your carbon footprint, gain extra kitchen space and improve your health. Just move your refrigerator to the basement. Since the basement is normally cooler than the upstairs, the refri…

From what i'v read, freezers are designed to be placed in ambient temperature greater than +10C. There are specificially designed freezers that can withstand up to -15C ambient temp: https://home.liebherr.com/en/lva/products/household-applianc... A guy on the phone that sells used freezers told me that compressor has some liquid that gets thicker when temperature drops below X and compressor has to work harder. The o…

Uhh, if your basement frequently gets below 0 °C, you have far bigger problems than the freezer. This should normally not happen unless you're living somewhere in the Arctic.

Re: How long does a freezer stay frozen when the power goes out?

#176

Post by KSteffensen »

NegativeLatency wrote: post #117
Dylan16807 wrote: post #110

Earlier quoted context omitted.

Is the efficiency benefit bigger than getting a different model or taping some styrofoam to the outside of the fridge?

I’d hazard a guess that most of the losses are from when you open the door and the seal around the door. Also while cooler than ambient my fridge and freezer don’t feel cool to the touch so I think that the walls are thick enough. Otherwise fridges and freezers would ship with thicker insulation.

There's a tradeoff between thicker insulation and space in the freezer

Re: How long does a freezer stay frozen when the power goes out?

#177

Post by distances »

throw_away wrote: post #96
geofft wrote: post #92

Earlier quoted context omitted.

This seems like a decent idea if the thing that's in your fridge is ice cream, but not if it's ingredients for cooking meals. Whoever does the cooking is going to spend a ton of time running up and down while stuff overcooks, and then they'll be even more tired and get more complaints from the rest of the family. So you should be absolutely sure that you have an equitable family dynamic and that everyone agrees that…

Perhaps a smaller L1 cache in the form of a mini-fridge could hold the prep for a given meal or even day or so in the kitchen, while keeping the cold storage cold storage downstairs.

Most mini fridges as atrociously inefficient, so that would negate a part of the upsides.

Re: How long does a freezer stay frozen when the power goes out?

#178

Post by interactivecode »

cs02rm0 wrote: post #123
fouc wrote: post #105

Earlier quoted context omitted.

Turn down the burner as much as you can, or even off.

My three year olds can trivially turn the burners up, or pull the pans down.

that is a child problem not a stove problem

Re: How long does a freezer stay frozen when the power goes out?

#179

Post by distant_hat »

an-allen wrote: post #154

Hi. Actualexperience here... it depends on the ambient temperature and how much stuff is in said freezer. So heres a data point: Freezer: normal upper level refrigerator freezer chock full of frozen fish caught on holiday in Alaska. Place, Time: Houston, TX, Late Summer, Hurricane Igor just hit and knocked our power out for 14 days. Findings: We kept the freezer shut and at about 4-5 days the fish was noticeably thaw…

Why not cook everything at that point and throw a feast. We've done this in India with an extended power cut.

Re: How long does a freezer stay frozen when the power goes out?

#180

Post by cozzyd »

Someone1234 wrote: post #10
at_a_remove wrote: post #8

Personally, I throw blocks of dry ice in there as soon as the power has been out a few hours, just in case. Beats regular ice all the way.

How do you safely handle dry ice? I'm legitimately asking, I know retailers sell it with big warning labels but I wouldn't know how to transport it, move it, and similar.

If you want to make a sound you'll never forget, put some dry ice on a metal sheet.
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