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.
How long does a freezer stay frozen when the power goes out?
21–30 of 384 posts
Re: How long does a freezer stay frozen when the power goes out?
#22Personally, 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.
Re: How long does a freezer stay frozen when the power goes out?
#23Related ... the last time I was in the market for a chest freezer (a "deep freeze") I wanted one that showed a log of temperature over time ... This, essentially, does not exist. It appears that there are laboratory freezers that support this (very simple) feature, but they are relatively small and very expensive . A better way to go is an electricity monitor on the plug, where you track electrical power over time an…
You could just freeze a cup of water, and then stick a penny in top of it. If you ever come back to find your penny embedded or at the bottom of the cup, you know your freezer thawed out at some point
Re: How long does a freezer stay frozen when the power goes out?
#24Personally, 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.
Re: How long does a freezer stay frozen when the power goes out?
#25If you can restock the freezer with ice, you can keep it cold for several days easily. Spoken from experience, thanks PG&E.
Where do you get ice if you are out of power?
Re: How long does a freezer stay frozen when the power goes out?
#26Related ... the last time I was in the market for a chest freezer (a "deep freeze") I wanted one that showed a log of temperature over time ... This, essentially, does not exist. It appears that there are laboratory freezers that support this (very simple) feature, but they are relatively small and very expensive . A better way to go is an electricity monitor on the plug, where you track electrical power over time an…
Such data might be interesting to look at, but as long as the freezer does its job (aka keep everything stored within it fully frozen), what's the point in having that data?
Re: How long does a freezer stay frozen when the power goes out?
#27Related ... the last time I was in the market for a chest freezer (a "deep freeze") I wanted one that showed a log of temperature over time ... This, essentially, does not exist. It appears that there are laboratory freezers that support this (very simple) feature, but they are relatively small and very expensive . A better way to go is an electricity monitor on the plug, where you track electrical power over time an…
Re: How long does a freezer stay frozen when the power goes out?
#28You want the contents to remain BELOW 0C, not hovering at 0C while everything melts. You can do this by adding some salt-water bottles, which have a lower melting point, and will therefore absorb a lot of heat (heat of fusion) well below 0C. Eg add 250g salt/liter gives melting point of -18C. Of course you waste some space on useless salt water vs potable - maybe there are better alternatives, eg fruit juice? Milk? H…
Your basic point makes sense to me though of course thawing isn't even.
ADDED:
Doing the calculation. It takes 334 joules to melt 1g of water vs. about 4 joules to raise that same gram of liquid water 1 degree. Freezer temp is supposed to be about -18 degrees Celsius.
So the latent heat of melting is a bigger deal than a few degrees of raising liquid temperature. So you should have ice packs maybe somewhere in the -10 degree range which is what I assume commercial ice packs do.
Re: How long does a freezer stay frozen when the power goes out?
#29Related ... the last time I was in the market for a chest freezer (a "deep freeze") I wanted one that showed a log of temperature over time ... This, essentially, does not exist. It appears that there are laboratory freezers that support this (very simple) feature, but they are relatively small and very expensive . A better way to go is an electricity monitor on the plug, where you track electrical power over time an…
Freeze cup of water with some red food coloring in it. Turn upside down. If you ever come back to a freezer that looks like it’s covered in frozen blood you’ll know.
Re: How long does a freezer stay frozen when the power goes out?
#30If you have extra space, using it to store something dense that has a high specific heat and is inexpensive is easy: use ice. (Glaciers take a -long- time to melt!)