It isn't always,
but the advantage of putting it there is that heat (hot air) rises.
You'ld rather not have that hot air heating up the body of the refrigerator.
The actual role of the cooling coil behind (or underneath in some cases as well as inside the side walls on some models) is to dissipate the heat collected from INSIDE the refrigerator as a result of the cooling cycle. If you would like more information on the subject, please follow the related links below to "How Stuff Works" The motor typically dissipates heat through a separate heat sink to prevent from excess heat being reintroduced into the refrigerator.
The cooling coil may be bad dirty, The coil is on the back or under the bottom or the fridge. Find it it and clean out the dust/dirt with a vac and brush.
Cooling coil yes uses CFC's. They destroy ozone.
A fluid is passed around a copper pipe wound into a coil, the coil is covered in ethenol (or another liquid with a low boiling point) as the ethenol evapourates it cools the pipe in turn cooling the fluid inside, working much the same way as sweating, the coil aspect saves space and increases surface area.
The coil.
Condenser coil
Your compressor is not working. Through evaporation compressors cool the evaporator coil and the fan blows air across it. So if the fan is blowing hot air the compressor is not cooling the coil. But check to see if the dial inside the fridge is turned to "more cold" , that turns the compressor on.
A radiator
Calculate condenser and coils
definitely, when air passes thruogh a cooling coil then moisture content of the air is increase b'coz condensation take place...
they get to hot/there is not enough cooling
To cooling air passing through in room