Thetfordⓘ advises fitting winter covers over the ventilation grilles of absorption refrigerators in motorhomes and caravans when the outside temperature drops below 6 degrees. For some refrigerator series, the manual specifies a threshold of 8 degrees. The covers protect the cooling system from excess cold air, whereas in summer the same grilles must remain open. On Dometicⓘ RM10 models running on gas, only the lower cover may be fitted; on electric power, both covers can be used. Compressor refrigerators, increasingly common in new motorhomes, do not require this measure.
