You will find an RV refrigerator climate control switch on most RV refrigerators. The climate control switch (sometimes called a humidity switch).is used to control frost that may collect during very high humidity situations.
The RV refrigerator climate control Switch controls a 12-volt heat tape behind the metal frame around the refrigerator and freezer doors. Much like a cold glass of water sweating on a humid day, the cold frame around the doors can cause water condensation to form and accumulate and even drip off the front of the refrigerator in high humidity conditions.
If you are having a problem with excessive frost buildup check to make sure the frost switch is on. The location of the Climate Control Switch varies from brand and model but is usually labeled.
If you are boondocking you may want to set the frost switch off.
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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