In this post we will talk about one of the most common problems with your kitchen refrigerator – the freezer looks fine but the refrigerator part is warm.

Before we go further let me explain the basic performance of the refrigerator.

Your refrigerator could be made by Whirlpool, GE, Frigidaire or Maytag – it does not matter.

The cooling coil (aka evaporator coil) is located in the freezer behind the back panel.

The evaporator fan is distributing the cold air through the cooling coil into the freezer and, through the damper control, into the refrigerator, causing the refrigerator to cool down as well.

If anything goes wrong with the cooling coil in the freezer, wrong temperature in the refrigerator is more visible and gets your attention first due to a very big temperature difference in the freezer (normally -5°F to 6°F) and refrigerator (36°F to 40°F).

So the problem as it looks to you is: the freezer is fine but the refrigerator is warm.

Well, the cause of this problem could be very different and now we will go over the first one – a faulty defrost system.

As the evaporator coil cools down, the frost builds up on the coil.
If it does not defrost periodically then the excess frost will block the air flow though the cooling coil, affecting proper distribution of the cold air and causing an increase in the temperature (the fresh food compartment first).

The classic defrost system (we are not talking now about refrigerators operated by electronic devices) consists of three parts: the defrost timer which calls for defrost on certain time intervals, the defrost heater which should melt the frost and the defrost thermostat which senses the cooling coil temperature and operates with the electric current to the defrost heater.

The first and most important sign of a faulty defrost system is a frost build up on the back panel in the freezer.

How to find out which part of the defrost system is bad?

Based on my own experience, I would recommend the following procedure:

1). Locate the name plate with the model number of the refrigerator.

2). Type the model number in the search box, click the “search” button and you will be directed to the break down diagrams.

3). Using the break down diagrams, locate the defrost timer.

4). Using a flat screwdriver, slowly turn the shaft in the middle of the defrost timer clock wise until it clicks to switch from the cooling cycle to the defrost cycle.

5). Wait about 10 to 15 minutes, open the freezer door and see if you can hear a sizzling noise. If you can, then the problem is the defrost timer which has to be replaced.

If there is no such noise, go to the next step…

DO NOT FORGET TO UNPLUG THE REFRIGERATOR!

6). Remove the back panel in the freezer, unplug at least one wire on the defrost heater (you can locate it using the break down diagram) and check continuity across the defrost heater wires.

If it’s open, the defrost heater is bad and has to be replaced.

If it has some resistance, then the problem is the defrost thermostat.

You can check the defrost thermostat continuity only if it’s frozen because if it’s warm, it should be normally open.


Best regards.
Gene.