Where is the defrost timer located for my GE GS25jfmc fridge

Hello and Welcome to FixYa!
Refrigerator mal function can be due to several reasons...To trouble shoot poor/no cooling problem, you need to carefully check all the below quoted possibilities one by one:

• Start Relay (Compressor Clicking won't Start in case of faulty).
• Bad/dirty Condenser.
• Defrost timer Settings.
• Cold Control Settings.
• Defrost (Ice built up on the evaporator coils that chokes the air flow to the freezer/refrigeraot compartment).
• Evaporator Fan.
• Main Control Board mal function.

You need to cross check all above quoted possibilities one by one to locate/trouble shoot the problem.

Best of Luck,

Your token of appreciation in form rating will be highly obliged.

Concerned.

DEFROST PROBLEM The evaporator coil behind the cover on the back wall inside the freezer will ice up under normal conditions. Every 8 to 10 hours for around 20 minutes the defrost timer (or in most newer models the electronic adaptive defrost control) will turn the defrost heater on to melt the built up ice. There is a defrost thermostat which prevents the heater from overheating the freezer by breaking the heater circuit when the temp reaches close to 32 degrees F. The entire cooling system shuts off during the defrost cycle and starts back when the timer advances through the cycle.
If this ice is not melted it will continue to build up until the air can’t flow over the coil to circulate the cold air through the freezer and into the fridge. The temperature change in the fridge is usually noticed first followed by the freezer.
If the defrost thermostat is bad, it can prevent the heater from coming on OR it won’t turn the heater off when it gets too warm. It is clamped to the evaporator coil at the top to sense the temp. If it appears to be misshapen it is bad. With an ohm meter it should show continuity when cold and none when warm. You can also bypass(disconnect the two wires plugged into it and twist them together) the thermostat to see if the heater comes on then. If it does then you know the thermostat is bad and needs replaced.
The defrost heater is located on the evaporator. It is in a tube which is at the bottom and can also go up the sides of the evaporator. On some types you can see a burnt spot if it’s bad. With an ohm meter it should show continuity from end to end when disconnected from the wiring in the freezer. You can also test the wiring for voltage when it’s in the defrost mode.
If you have a defrost timer you can test it. It can be located under the fridge behind the kick panel on the front. Some are in the fridge with the controls at the top. 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 because that means the timer is not running. If it doesn't, check the heater and defrost thermostat. Turn the timer again till everything starts back up to end the defrost cycle.
If you have an adaptive defrost control instead of a timer, replace it if the heater and thermostat test good. It is located in the fridge with the controls in some models and on the back in others. You can post your model number into one of several appliance parts sites on the internet and search for defrost components to find your parts.

The evaporator coil behind the cover on the back wall inside the freezer will ice up under normal conditions. Every 8 to 10 hours for around 20 minutes the defrost timer (or in most newer models the electronic adaptive defrost control) will turn the defrost heater on to melt the built up ice. There is a defrost thermostat which prevents the heater from overheating the freezer by breaking the heater circuit when the temp reaches close to 32 degrees F. The entire cooling system shuts off during the defrost cycle and starts back when the timer advances through the cycle.

If this ice is not melted it will continue to build up until the air can’t flow over the coil to circulate the cold air through the freezer and into the fridge. The temperature change in the fridge is usually noticed first followed by the freezer.

If the defrost thermostat is bad, it can prevent the heater from coming on OR it won’t turn the heater off when it gets too warm. It is clamped to the evaporator coil at the top to sense the temp. If it appears to be misshapen it is bad.
With an ohm meter it should show continuity when cold and none when warm.
You can also bypass(disconnect the two wires plugged into it and twist them together) the thermostat to see if the heater comes on then. If it does then you know the thermostat is bad and needs replaced.

The defrost heater is located on the evaporator. It is in a tube which is at the bottom and can also go up the sides of the evaporator. On some types you can see a burnt spot if it’s bad. With an ohm meter it should show continuity from end to end when disconnected from the wiring in the freezer. You can also test the wiring for voltage when it’s in the defrost mode.

If you have a defrost timer you can test it. It can be located under the fridge behind the kick panel on the front. Some are in the fridge with the controls at the top. 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 because that means the timer is not running. If it doesn't, check the heater and defrost thermostat. Turn the timer again till everything starts back up to end the defrost cycle.

If you have an adaptive defrost control instead of a timer, replace it if the heater and thermostat test good. It is located in the fridge with the controls in some models and on the back in others.
You can post your model number into one of several appliance parts sites on the internet and search for defrost components to find your parts.

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The evaporator coil behind the cover on the back wall inside the freezer will ice up under normal conditions. Every 8 to 10 hours for around 20 minutes the defrost timer (or in most newer models the electronic adaptive defrost control) will turn the defrost heater on to melt the built up ice. There is a defrost thermostat which prevents the heater from overheating the freezer by breaking the heater circuit when the temp reaches close to 32 degrees F. The entire cooling system shuts off during the defrost cycle and starts back when the timer advances through the cycle.

If this ice is not melted it will continue to build up until the air can’t flow over the coil to circulate the cold air through the freezer and into the fridge. The temperature change in the fridge is usually noticed first followed by the freezer.

If the defrost thermostat is bad, it can prevent the heater from coming on OR it won’t turn the heater off when it gets too warm. It is clamped to the evaporator coil at the top to sense the temp. If it appears to be misshapen it is bad.
With an ohm meter it should show continuity when cold and none when warm.
You can also bypass(disconnect the two wires plugged into it and twist them together) the thermostat to see if the heater comes on then. If it does then you know the thermostat is bad and needs replaced.

The defrost heater is located on the evaporator. It is in a tube which is at the bottom and can also go up the sides of the evaporator. On some types you can see a burnt spot if it’s bad. With an ohm meter it should show continuity from end to end when disconnected from the wiring in the freezer. You can also test the wiring for voltage when it’s in the defrost mode.

If you have a defrost timer you can test it. It can be located under the fridge behind the kick panel on the front. Some are in the fridge with the controls at the top. 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 because that means the timer is not running. If it doesn't, check the heater and defrost thermostat. Turn the timer again till everything starts back up to end the defrost cycle.

If you have an adaptive defrost control instead of a timer, replace it if the heater and thermostat test good. It is located in the fridge with the controls in some models and on the back in others. You can post your model number into one of several appliance parts sites on the internet and search for defrost components to find your parts.

This sounds like a problem with the defrost circuit. It is likely that the evaporator coil is clogged with ice due to the defrost heater / circuitry not functioning. This can be caused by a failure of any one or more of the following components:

1) Defrost timer. Defrost timer may be "stuck" - failing to advance from a cooling cycle to a defrost cycle. May be found in the toe space of many fridges, but not all.

2) Defrost terminator. This is a thermal sensor that is secured (usually with a clip) to the refrigerant line close to the evaporator coil in / behind the freezer compartment. If this component fails to detect a rising temperature, it never allows the fridge to return to the cooling mode again.

3) Defroster Heating coil. This is a simple, relatively low wattage heater secured to or near the evaporator coil. It is powered through the defrost timer and shut off by the defrost terminator. If the coil is burned out or otherwise "open", it will not heat to melt ice buildup on the evaporator coil.

4) Fan. The fan is located near the evaporator coil. If the fan is unable move air from the freezer to the fridge, the compressor runs endlessly because cold air is not directed into the fridge compartment - where the thermostat is located.

5) Condenser coil. If the condenser has a "furry jacket" it's long overdue for a cleaning. Gently vacuum lint / dust / dirt collected on the coil to increase efficiency. This is probably not the problem - but it probably needs to be done anyway.

Most of these steps will require hand tools, schematics (specific to your model), electrical test equipment, etc. Be careful to not use sharp instruments that may puncture refrigerant lines or electrical insulation. Allow the ice to defrost with the fridge powered off with the freezer door opened, or place a pot of hot water inside, hair dryer directed at the coil, etc. Access to the evaporator coil is usually from the freezer compartment (back wall) and will require removal of any ice maker installed.

I hope this helps!

twist your defrost timer with a screwdriver clocwise till it will click and compressor shut off, check voltage on defrost heater. You should have 120volts.When wait 20 min if compressor start up back and defrost heater is off ...your timer is fine. It can come on early then 20 min....
P.S. defrost heater located on the bottom of the coil, also make sure your defrost thermostat is frozen when you going to check voltage on your heater. Thermostat located on the top of your coil.

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

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

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, ie 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 of fridge)

The unit is in trouble, but you're right, it's not dead yet. Check the condenser coils, clean them if needed. They must be able to dissipate the heat. Check the condenser fan, must be unobstructed, turn free, a drop of oil may help if it's dying. You may have a failed Defrost system. That failure causes the evaporator coils to ice over, choking off the airflow inside the box. If you shut it down, and train a heatlamp on the rear panel of the freezer (inside) and a small flood occurs, then the defrost is it. After the thaw, you can start the box, and it will cool again until it ices over again. the right answer is to fix the defrost problem in that case. The defrost timer can fail and cause this, if you locate the timer, (usually behind the grille) and advance the center shaft with a screwdriver, slowly until a click and the compressor stops, give it an hour and advance again to restart, you may get a defrost if all else is ok. (replace the timer)