In article , Harry Bloomfield
writes
Brian Reay laid this down on his screen :
Virtually motorhome Ive looked at has a three way fridge, gas, 12v, 240v


I have seen gas/240v only, but the more desirable ones are the 3 way
fridges. They run most economically cost wise, on 240v.

240v and gas use a thermostat, the 12v does not - they run flat out
continuously, barely able to hold the temperature down.
The 12v is designed only for use in transit connected to the towing
vehicle. hey would flatten 12v batteries in next to no time. I have one
which is controlled by thermostat on 12v.
--
bert