Many Dometic brand RV refrigerators are equipped with a humidity switch. The humidity switch powers a small heating element around the freezer door. The purpose is to control frost that may collect during very high humidity situations.
The heating element is not on the refrigerator on/off switch, So as long as the humidity switch is on the heating element is drawing power even if the refrigerator is turned off.
The heating element draws around 6 amps that will drain a battery in just a few hours. If your battery goes down for no apparent reason, check this switch!
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