Why is my freezer intermittently working?

"Hi,

When you say that the evaporator fan was blowing air that was far from cold, did you happen to notice whether the compressor motor was running at the time?

The compressor, compresses the liquid refrigerant and pumps it through the evaporator as a gas. The evaporator fan blows air across the evaporator coils which has the well below freezing point gas passing through it, thereby cooling down the freezer and the fridge

If the compressor was running there may be a loss of refrigerant in the system or a problem with the compressor.

If it was not running then there may be a problem with the defrost thermostat for example, keeping the fridge in the defrost state

Here is a link to the list of possible causes to your problem

If it is now nearly back to normal, (it may take the freezer nearly 24 hours to get back to the correct temperature), all you can do is to keep checking the temperature in the freezer section to ensure that it stays at the correct temperature. Be aware that once every 8 -12 hours (varies with manufacturer) the fridge will go into its' defrost cycle, i.e. the compressor will be stopped and the freezer temperature will go up to 33-35 degrees F (0 - 1 C) so as to allow the frost on the evaporator unit to melt. (Don't get confused if the compressor is stopped as the correct operating temperature may have been reached. Usually it doesn't stay stopped for long as temperature changes occur when the doors are opened etc causing it to start again) To speed up this process a defrost heater is turned on as well. The defrost cycle is control by thermostats (or thermistors) and the control board which determines the time it should take in conjunction with the thermosat/thermistor. It shouldn't be longer than 20-30 minutes, after which the compressor will be started again to drive the temperature back down to 0 degrees F. (-18C)

You will have to wait to see when and if it fails again and then check what is occurring with the compressor. If it is running, feel the evaporator coils in the freezer (use a dry cloth and the back of the hand so that you don't get ice burns), normally it should be freezing.

If it is not running and has been off for a long time (more than 30 minutes or so to allow for the defrost cycle) you will have to start checking the items in the link above.

Sorry about the length of the reply but thought it would be easier if you had a grasp of what should occur.

Apologies if you knew all this."