Frost forming on sides of fan in Hotpoint auto-defrost fridge freezer

Hi @fridgemc

Looking at the parts for your refrigerator, as there doesn’t seem to be a control board perhaps there is a problem with the thermostat.

In most refrigerators the compressor and evaporator fan will stop when the set temperatures have been reached and start again once the temperatures have risen a few degrees to get the temperatures back down to the set temperature. Maintaining the set temps is harder due to normal activity i.e. doors opened a lot so the compressor will be running for longer to compensate for the loss of cool air when the doors are opened.

First thing in the a.m. may be a good time to check if it is running but it doesn’t mean that it won’t be. Place an appropriate thermometer in both compartments to check on the actual temperatures. Usually the freezer is -20 deg. C and the refrigerator is 3-5 deg. C.

The defrost cycle usually occurs once every 8-11 hours. The actual time period varies between manufacturers depending on the design. During this time the compressor and evap fan are turned off and the freezer temp is allowed to rise to 0 deg. C to enable the ice build up on the evap unit to melt and drain away to the evaporator pan under the fridge. The melting time is sped up by turning on a defrost heater under the evap unit as you don’t want the food to even begin to thaw.

When the temp reaches 0 deg. C a defrost thermostat (or thermistor) operates and either signals a control board (or maybe it is the thermostat in your model) to turn the heater off and the compressor and evap fan back on again to drive the temps back down to the set temps. The defrost cycle time is usually 15-25 minutes

The parts list for your model shows the thermostat when trying to find the heater and also there are no other “sensors” or thermostats shown so maybe it relies on the thermostat for everything.

Hopefully this is of some help.