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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?

#141

Post by [deleted] »

rollulus wrote: post #135
galkk wrote: post #112

> When opening an empty upright freezer, all the cold air can just "fall out" I recently found that the ice-cream refrigerators of street vendors (and everything else that is being sold when the doors are frequently opened) are opening on the top for that exact reason - to not let cold air "fall out" (because cold air is on the bottom)

I find it weird that his new freezer has open compartments. Mine, and the majority a quick google search showed, have boxes with the opening on top in each compartment, you can slide out. I don't have the numbers but my intuition says that it's more energy efficient.

[deleted]

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

#142

Post by _v7gu »

shortandsweet wrote: post #128
contingencies wrote: post #59

It depends on the thermal mass of the contents, the effectiveness of the insulation, and the external ambient environmental temperature. In real world use, it also generally depends on (1) how frequently and for how long you open it, and (2) whether it's top-loading (efficient) versus front-loading (inefficient). Source: My venture custom designed and built a refrigeration circuit with autonomous electronic managemen…

I keep a coffee mug filled with water in the freezer with a penny on top.

Wouldn't the pressure from the penny bias your observatios from the mug?

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

#143

Post by pengaru »

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.

It's like pre-loading your refrigerator/freezer with a sack of ice. If your power goes out long enough for your food to spoil, what will you do? Well, maybe you'll go buy some sacks of ice to throw in there until the power turns back on.

Ok, if you have the space to spare, why wait for the failure to go fetch the emergency ice? Just fill the empty space with ballast water and you're ahead of the problem.

Once the thermal mass is at the desired temperature, it will help bring newly introduced items to the desired temperature faster, not slower.

The only time it slows down the cooling is when first introduced @ a warmer temp, or when there's been a failure for long enough to let everything warm up. But note that in the failure scenarios, the thermal mass helps keep the space cool for longer than had it not been there. Just remove the warmed ballast when the failure is over to let the perishables re-cool first, then reintroduce the ballast when appropriate ... perhaps even pre-cooling it elsewhere first.

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

#144

Post by chopin »

BrandoElFollito wrote: post #134
efficax wrote: post #122

Earlier quoted context omitted.

in the US natural gas stoves are very common. There is some risk when frying on high heat that you could start an oil fire... Never used induction but gas offers very fine control of heat with a nice stove, especially compared to electric which relies on radiant heat from a coil and cannot change temperatures rapidly

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.

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

#145

Post by philwelch »

galkk wrote: post #112

> When opening an empty upright freezer, all the cold air can just "fall out" I recently found that the ice-cream refrigerators of street vendors (and everything else that is being sold when the doors are frequently opened) are opening on the top for that exact reason - to not let cold air "fall out" (because cold air is on the bottom)

This is also why the Trader Joe’s freezer/refrigerator section is designed the way it is. Turns out that a chest freezer/refrigerator with no top on it at all isn’t that much worse than a standing freezer/refrigerator with a door that gets opened and closed over and over again.

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

#146

Post by [deleted] »

wutwutwutwut wrote: post #107
contingencies wrote: post #59

It depends on the thermal mass of the contents, the effectiveness of the insulation, and the external ambient environmental temperature. In real world use, it also generally depends on (1) how frequently and for how long you open it, and (2) whether it's top-loading (efficient) versus front-loading (inefficient). Source: My venture custom designed and built a refrigeration circuit with autonomous electronic managemen…

Hm did you read the article? I ask because you're just repeating things brought up in it.

[deleted]

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

#148

Post by SCAQTony »

Freezer: 8-cubit feet of space totally full! If you keep the door shut and don't open it the food will last about 12-hours.

This happened to me this week. Use dry ice to keep the food fresh. Dry ice costs $1.00 a pound, you need 25 pounds total, five for the freezer. This solution will work for about 12-hours.

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

#149

Post by ramraj07 »

shortandsweet wrote: post #128
contingencies wrote: post #59

It depends on the thermal mass of the contents, the effectiveness of the insulation, and the external ambient environmental temperature. In real world use, it also generally depends on (1) how frequently and for how long you open it, and (2) whether it's top-loading (efficient) versus front-loading (inefficient). Source: My venture custom designed and built a refrigeration circuit with autonomous electronic managemen…

I keep a coffee mug filled with water in the freezer with a penny on top.

Have you seen how long this setup takes before it'll trigger a change? Ive left glasses of frozen water to thaw and they most definitely don't thaw evenly. They also take way more time to thaw than any regular food product due to the significant heat/surface area ratio difference.

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

#150

Post by OJFord »

TheSpiceIsLife wrote: post #47
Mathnerd314 wrote: post #31

Earlier quoted context omitted.

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.

Chilling food super swiftly / immediately is rarely a concern for regular home residents. It is a public health concern at scale . Two overlapping but divergent scenarios.

Chilling drinks quickly is though.

(Or gazpacho, thought that might be shot down as a bit niche though. But it is lovely this time of year (in the Northern hemisphere)!)

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