Frost Free Fridges and Fridge Freezers

For those of you who have a desire to know how things work and really understand what goes in with your various appliances, you will find the following interesting.  However, if you are not a technical kind of person, you might still be interested to know you could still find problems with a frost free appliance.Safety, as with all electrical appliances, is very important but you must ensure that you have unplugged your fridge or fridge freezer before you attempt to touch anything.  Electricity, coupled with the high possible of water being around, can and will kill you.  Take a moment to think about your safety, and don’t just rush in to something you may well regret later.

The Basics

In a normal freezer you can see the cooling pipes (evaporator) as they quite often form the shelving units.  You will clearly be able to see the ice/frost building up inside the freezer compartment.  Very simple to defrost, just turn off the appliance, and get ready to mop up as the ice melts.

However, with a frost free appliance, you are unable to see the cooling evaporator as they will be concealed behind the cover at the back or around the inside the freezer.  The evaporator is formed of pipes as described above, but with fins attached.  Air is drawn from inside of the freezer via an electric fan through the finned evaporator.  This process is continued on a loop, with air being moved by the fins.  A small heater is in place and is activated as and when any frost starts to build up on the evaporator.  Any water produced will run into a drainage hole onto a tray, from where it will evaporate. 

 If your appliance is a combined fridge freezer, it is quite likely that the fridge compartment has no working parts of its own, and refrigeration will be controlled by the temperature, if it starts to get too warm, the air is automatically cooled to the right temperature.

Problems with temperature control

It is unlikely that faults can be diagnosed without the assistance of an engineer.  If you are not sure what you are doing, you could cause more damage in your endeavour to repair the problem.  It is not uncommon for a fault to seem to be corrected, but over a period of time it may return and will need further investigation and repair.  If you have paid for an engineer to repair the fault, you can recall them and ask them to rectify the problem.  It is unlikely that you will have to pay again for the repair, especially if it is exactly the same fault.

Parts that could go wrong


As explained above, the temperature of your appliance is controlled by an evaporator, condenser and compressor.  Most frost free appliances will have a fan, which you should be able to hear running.  However, if you don’t hear the fan running, you cannot just assume the problem is with the fan itself.

Fans are built to switch off when the door is opened, or when the correct temperature is reached.  They are very reliable and, in fact, generally don’t need to be replaced unless they have become too noisy for comfort.

Defrost heaters:

As described above, the heater is designed to activate should frost start to form on the evaporator.  A further heater will be located near to the drain hole to ensure the drain does not freeze and, therefore, cause a blockage.  These are probably protected by a thermal fuse, and this may be the cause of a problem should you notice that ice is forming, indicating a problem with either of the heaters.

Control module:

The control module, or PCB, is the electronic controller for your appliance, ensuring correct temperatures are reached. If a problem is located within this module, it is likely the whole unit will need to be replaced.

In order to ensure you keep your fridge or fridge freezer working correctly, and giving you many years of service, you must play your part as well.  Keep both compartments clean, and check that out of date items have not slipped to the back of fridge.  If left too long, apart from a nasty smell, they can actually become rancid and will be very difficult to remove without leaving a stain on the inside of the cabinet.

It is essential that there is plenty of ventilation around the appliance, as frost free fridge freezers or stand alone freezers require a steady airflow.  As part of your general housekeeping for this appliance, it is a good idea to clean underneath as often as possible, especially if you have pets, as dust accumulates in this area, and can cause a blockage and therefore overheating.






Disclaimer: The information provided has been prepared as a guide only and the steps taken are likely to vary for different appliance models. We strongly recommend using a qualified engineer to undertake major repairs and fault finding.


Need help?