What turns on the evaporator fan? I have a 5 year old GE profile bottom freezer fridge. I have discovered that the defrost timer is faulty. The defrost heater works and the evaporator coils frost up ok but the fan does not run what could the problem be?

You have a defrost problem. Locate your defrost timer while the unit is iced up and turn it until you hear a defined click. At this point open the freezer and listen for ice cracking. If Ice starts cracking then it's your defrost timer bad. If ice doesn't crack, then you have a defrost component bad ( heater and Bi-Metal) Ohm out your heating element and replace if there is no continuity. You can usually find defrost timer either under the front of the box, in the fridge around the light or thermostat or sometimes in the back at the bottom. The dial on the timer can only be turned one way with a large flat head. You will hear the difference in the way the clicks sound for the defined click. Good luck.

It's freezer fan hitting with your bin drawer when it's over ice formed behind the freezer. It's due to malfunction of defrosting. Keep 5 degree thermostat setting. And check thermostat by turning counter clock wise. If shuts off the fridge, it's working. If not replace thermostat. Check defrost timer set in proper setting. Once defrost cycle is good, no banging sound will be there. Thanks.

Hi,

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heatman101

once ice forms on the freezer coils there is no air flow. I had the same thing. I suspect your defrost cycle is compromised. Could be the bimetal switch, defrost timer or defrost heater element.

Your problem could stem from an issue with the defrost timer, the compressor or its attachments (e.g.: relay, capacitor, etc.), or the freezer/evaporator fan motor. Contact an appliance service company.

Air circulation problem. Evaporator fan in freezer moves some air to refrig. Either fan is not working or air passages are blocked with ice. If ice found, then a defrost component failure has occurred. Fix what you find.

depending on the model, 1-5 years. 5 reasons for fridge and/or freezer getting warm: 1- the evaporator coils are icing up and won?t let air circulate. 2- the evaporator fan is not working to circulate air. 3- there is no refrigerant in the system. 4- no power to fridge or compressor. 5- the condenser coils have no air circulation check under the fridge behind the vent. if it is too dusty or the fan isn?t working, it is not getting enough airflow to cool down. replace fan and/or vacuum out the dust. if there is no power to the fridge, the light will be off. if the compressor is not running, there is a defrost timer that cuts the power temporarily to the compressor to melt ice on the coils. it?s located under the fridge behind the bottom vent. If the timer is off and the compressor is not going, the compressor or the main board is bad and needs replacing. there is also a temperature sensor on the evaporator coils that tells the defrost coil to turn on and when to turn off. if the defrost timer is on but the coil is not heating up, replace the sensor. if it still won?t heat up, it?s the timer or the coil. the easiest way to tell if there is no refrigerant- the freezer wall is warm and the compressor is loud. if there is no refrigerant, it may be more cost effective to replace the fridge. if you feel no air coming from the freezer vent, the fan needs replacing. If you feel air moving in the freezer but not the fridge, the channel from freezer to fridge is blocked. if the freezer has air and the rear freezer wall has frost on it, the evaporator coils are iced up and need defrosting. causes: 1. low refrigerant 2. no fan 3. too much humid air in fridge/freezer due to door open or bad door seals 4. the condensate drain tube is clogged 5. defrost cycle not functioning properly if the seal around the door is ripped or not completely sealing, or there is condensation at the bottom or the walls of the fridge, replace the seal(s). no air, no fan. Replace if the refrigerant is low, it just needs a top off. but you need to be certified by the epa to move refrigerant, so get a professional. there defrost cycle starts with the timer. at a certain time of day for a specific time, the timer turns the compressor off and turns on the heater element located at the bottom of the evaporator coil. this stays on until the coil temp sensor reaches a certain temperature to let the timer know that the coils are defrosted and turns off the power to the element. the defrosted water drains to the condensate pan. if the timer is bad, it will never go into defrost, or never get out of it. if the element is bad, the coils will never defrost. if the temp sensor is bad, it?ll go into defrost, but it will either tell the timer that it?s always frozen or already defrosted, resulting in the element never turning on (stays frosted) or never turning off (eventually burning out the element). defrost solutions: unplug the fridge. remove the wall of the freezer that is frosted/icing up. use a hair dryer to melt the ice. do not get too close. you will see a drain under the evaporator coil. make sure it is not blocked. the water should run freely to a condensate pan under the fridge that evaporates the condensation with the hot line from the compressor. once the coil is free of ice, frost, and water, replace the panel and repair any of the problems that caused the icing up. plug the fridge in and turn it on. If it frosts up within a week, there is still an issue that not been taken care of.

Your evaporator coils frost up in normal use and every eight hours or so the entire unit shuts down and the defrost heater comes on to melt the frost. This cycle last about 20 minutes. The melted frost drips into a drain pan and through a drain tube to the drain tray under the freezer/refrigerator where it's evaporated by the condenser fan.

If the evaporator coils behind the back panel of the freezer are icing up because of auto defrost failure that will stop the circulation of cold air and eventually affect the freezer too.

check defrost timer, defrost heater, defrost thermostat. In most newer models the timer has been replaced by an electronic control board. If the heater and thermostat are ok it’ll be the control.

You can turn the defrost timer till it clicks and everything shuts down. The heater should now come on. If it does, replace the timer. If it doesn't, check the heater and defrost thermostat. Turn the timer again till everything starts back up to end the defrost cycle.

How to check everything
http://www.acmehowto.com/howto/appliance/refrigerator/refrigerator.php

If freezer is icing up, you might have a defrost problem. Frost free models have a heating element that is controlled by a timer to automatically defrost ice, defrost timer turns on defrost heating element every 12 hours to melt ice in freezer and allow good air flow.
You can test defrost element with an ohm meter(located inside freezer coils-will have two wires going to a plug connection), if OK replace defrost timer (located in various places depending on make and model

Sounds like a typical air flow (circulation) problem. This can be due to an evaporator fan not working, a frozen up coil not allowing air flow over it (due to failed defrost system, etc.) or even the damper for the fridge section stuck closed not allowing cold air from the freezer in. The first thing is to check the evap. fan to make sure it's running. It's easy to take the rear interior of the freezer section off and check for fan operation, solid ice on the coils, etc. If the coils have a nice white frost pattern all over then that's ok, but if they are frozen solid block where the air can't flow over them it's a defrost timer, defrost t-stat or defrost heat element (not likely) issue. Usually it's the t-stat or timer that goes out. The t-stat is easy to visually check to see if it's epoxy is "popped" out and of course a continuity check to be sure. The defrost timer is just a swap out sort of thing, not much to test there.