Freezing cold kitchen

[foxhole]

That may be so but there is no heat to absorb, the heat exchanger is used to prevent heat escaping a house by recirculating it, but there has to be a heat source to begin with.The heat exchanger is mainly used with underground pipes to draw heat from below ground where the temp is always constant, but there has to be a source of heat for it to work.
The 3 to 1 ratio quoted is in respect of it's efficiency at removing heat from a heat source , it cannot work where there is little of no heat source.

 

[ColJack]

of course there is heat..
it's a relative scale..
0°C is only 0 because somebody decided to measure temperature against the phase states of water..
at 0 it freezes and at 100 it boils..

if you're measuring in farenheight then water freezes at 32°F..

with a total lack of thermal energy, electrons stop moving.. it's something like -273°C..
so as long as one thing is colder than the other, the heat will transfer from the warmer thing to the colder thing until they are even..

 

[noseall]

The exchange of heat phenomena is old news, but extracting it is not as economical as you may think.

 

[foxhole]

Thats exactly my point, you might get a 3 to 1 exchange rate , but only where you are extracting from a good heat source, thats not what you can expect from sub zero air temp's.