Freezer temperature Q.

[NotReallyMyName]

Obviously hot weather has freezer running a bit more. After noticing that our built in kitchen freezer seemed to be almost permanently on, I decided to defrost it last night.

After wiping it out at 10 this morning, I switched it back on and by 11 it was down to -7, and now it's just reached -18.3 (according to an external thermometer with the probe in the centre).

It's still running ... at what temperature should it cut out ?

The dial is set to "1" from a possible "4" (and the super/fast freeze feature is off.

[Chris Hogg]

Recommended setting for a freezer is -18C IIRC

[Tim Watts]

I concur - though I set mine to -24 (and it *can* go to -36C! if you max it out)

[Brian Gaff]

If its a fridge as well, it may well be that part that is keeping it running. Brian

[tabbypurr]

-18 is the usual. They vary a few degrees in practice

NT

[Allan]

Bought a new freezer (standalone, under the counter) recently; it has a temperature display/control on the front. I wanted to check the temps, as no point in having it over cold as I was aiming for -18. I have a thermometer with a small digital display and a long wire with a sensor on the end so I can put the sensor inside and the display outside and can check the temps without having to open the door all the time (counter-productive!).

I found that I had to set the display control on the front to -15 to get the temps (according to the probe thermometer) to be near -18 otherwise the freezer was setting itself far too cold and using far too much electricity...

Just my 2p's worth.

[Huge]

Couldn't you have just bought one in a shop? There are are no restrictions on the sale of freezers that I'm aware of. :oD

[dennis]

8<

What did you check the thermometer against? IME cheap digital thermometers can be a few degrees out.

I think you can check it by putting a load of ice in brine + some extra salt as the ice dilutes it as it melts, in equilibrium it should be around -20C.

[Robin]

I think you have in mind that a saturated salt solution freezes at -21.1 degrees. It's a simple test to see if a freezer is well below -18.

You can get a solution that freezes at -18 degrees by weighing carefully the salt and water but I don't have the ratio to hand.

[NotReallyMyName]

Thanks for all the replies ...

It's just a freezer - not a fridge freezer.

I was testing it will a little digital thermometer used for checking aquarium temperatures.

Eventually, it got to -25, still running. But next morning, it was -19, and had stopped. It spent yesterday ping ponging between -9 when the door was opened, to -21. Currently at ... -20.

But yesterday the temperature in the house dropped a couple of degrees, which means it's able to lose heat slightly better ...

Main concern is that it;s at least 16 years old .... it was here when we moved in.

[Andy Burns]

What do these ice-breaker fish look like?

If the freezer only has air in it, the temperature will change pretty rapidly when the door is open ..

[tabbypurr]

Yup. It sounds serviceable, most likely.

NT

[Andrew Gabriel]

-18C is warmest a 3-star Freezer is allowed to run. Usually, they are at least a little bit colder, baring in mind the temperature is unlikely to be completely uniform throughout.

I accidently left my Hotpoint on fast freeze for a few days when it was quite new. It went below -40C (how much below I don't know). The thermometer had sucked all the liquid back into the bulb, and the lowest marking on the scale before that was -40C.

[Johnny B Good]

====snip====

That is the one temperature where the use of C or F is redundant. You could have simplified it to "-40" and let the reader choose their preferred scale. :-)

[Bob Eager]

I hate it when newspapers say "the mercury dropped to below -50". Mercury freezes before -40 ...

[Jethro_uk]

Mercury hasn't been used in thermometers for *years* ....

[Bob Eager]

Well, that too.

[Huge]

Another mindless literalist. Get your carer to explain "metonymy" to you.

[charles]

That applies to new ones, but plenty of mercury ones still exist.

[Jethro_uk]

Another mindless poster who can't quote.