How cold would it get?

[retro-man]

If a refrigerator compressor was allowed to run non stop for we shall say 3 or 4 days how cold would it get in the freezer? Would it get colder in a frost free or the standard freezer without the blower? I often wondered about this. Also the reason I am asking is because with the ice maker in mine running the freezer on fast ice sometimes it keeps the blower running to make ice faster. I do have a thermo in the freezer and it was -25 degrees. The martinis had turned to slush. This was from running overnight. Inquiring minds want to know.
Jon

 

[dj-gabriele]

The temperature would continue to get lower till you reach thermal equilibrium: the compressor moves the same quantity of heat that penetrates the fridge from the outside.

This is simplicistic because you need to take into account the compressor physical limits, environmental parameters and insulation.

The blower is there only to speed things up because forced convection is more efficient than natural convection at moving heat (or cold) from an area to another.
Eventually if you take two equal machines one with the fan and one without, you'd get circa the same final temperature, a little less in the one with the fan if the fan engine is in the cold cavity as the heat dissipated from the motor contributes to heat input and air friction due to the fan gives its (very small) contribute too.

 

[arbilab]

Well now we know the freezing point of a martini, eh?

There is an absolute limit, the boiling point of the refrigerant at max compressor suction. Temp won't go below that. But I don't know what that is, it depends on what refrigerant, compressor design and condition, high-side (condenser) temp/pressure.

 

[retro-man]

Thanks for the info guys. So probably its close to that point that no more cold would be introduced into the freezer. Thats about the temp most meat processing plants and frozen food plants work at so this must be about the point that they can go down to.
Jon

 

[DADoES]

 
Technically, cold is not introduced into the the freezer.  Cooling is achieved taking heat out of it.  

 

[arbilab]

Industrial processes can go well below what home appliances can.