power on , freezer not running?

My power is on however the green light is not ,and after being away for the weekend, everything is defrosted. Can this be a coolant top up is required or new compressor. I live in a static caravan and the heating was left/ on. I had no water freezing problem,only the freezer. The freezer seemed to attempted click in when i turned up the thermostate, but alas the green running light did not show. This is norfrost freezer about 5 years old, and i have lost the manual through moving homes

trevor dodwell
December 2010