Can you operate a deep freezer in an unheated garage during winter months with temperatures reaching -20c and all year round? Thank you

Hello Kirwin

No problem. There are no parts open to weather/temperature conditions outside the freezer.
There could be a slight problem with the door seals. Put a very thin layer of vaseline on them to protect the seals.

Success !

:)

The only real problem that I can forsee is the generation of water from the exterior coils. Dew point table (http://mvddaq.desy.de/~mvddaq/SC/Tdew.html)

The temperature in the cells is the temperature of the surface, below which ice or water will form.

You might invest in a compressor heating blanket. This might take a little work. Not sure if they are available for small compressors. It would extend the life.