How to replace sensors and control board

Manually defrost the freezer so it cools and you can see what part of the defrost system has failed. Here is a link to your MFI2269VEM6 Refrigerator Parts List=> HERE You will need to insure the evaporator fan is working=> W10162809 Evaporator Fan the defrost Heater=> Defrost Heater Assembly W10166768 and the defrost thermostat which apparently is attached to the evaporator fan wiring. If all of this checks out you will need to consider replacing the control board=> Main Control Board W10310240 I am pretty sure the defrost controls are in the control board. I am here if you have questions,
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solenoid for the ice dispenser flopper might get rusted, so the flop door would not close and freezer air would escape building up ice. need new solenoid assy for ice dispenser door and possible flopper.

It doesn't defrost

1. Defrost control board

If the defrost function is not working on your refrigerator it could be an issue with the defrost control board. This control board oversees several internal conditions and regulates the activation of the defrost cycle. A faulty board can be the primary reason your refrigeration unit is not transitioning to the defrost cycle. Over time, the buildup of ice on the evaporator coil will prevent the refrigerator and freezer from maintaining proper internal temperature. It is advisable to first check the defrost heater and the defrost thermostat for continuity prior to replacing the defrost control board.

1. Main control board

A possible cause for a refrigerator not defrosting, especially on more modern units, is the main control board. The main control board acts as a "brain" for the unit controlling the defrost cycle, compressor, and run time, and essentially acts in place of the defrost timer. The control board can be tested using an ohm meter for functionality and will need to be replaced if bad.

1. Defrost timer

If the refrigerator is not defrosting the timer could be malfunctioning. Numerous times throughout the day the defrost timer should cycle the defrost heater on as a means to melt frost buildup on the evaporator coils in the freezer. If this timer does not cycle on, then it may be faulty and require replacement.

1. Defrost heater assembly

If your refrigerator is not defrosting accurately this could be an indication that your defrost heater assembly has failed. This could cause the frost to accrue on the evaporator coils, eventually blocking the airflow resulting in the unit not cooling properly. The defrost heater assembly can be monitored for continuity using an ohm meter and will need to replaced if there is none present.

1. Defrost thermostat

Another cause of your refrigerator not defrosting is a faulty defrost thermostat. A requirement for the defrost heater to activate to melt away frost on the evaporator coils is a functional defrost thermostat. The defrost thermostat senses the temperature of the evaporator coils and initiates the thawing process by activating the defrost heater. If the thermostat is faulty, it will not sense the lowering temperature of the coils and will not turn on the heater, resulting in an advanced frost build-up. The defrost thermostat can be checked for continuity by using an ohm meter; if there is no continuity the damaged part will need to be replaced.

1. Defrost sensor with fuse

Another possible cause of a refrigerator that does not defrost properly is a defrost sensor with a fuse. If the defrost sensor fails, the fuse acts as a one-time-only fail safe for the sensor -- if the sensor does not shut off the defrost heater, the fuse will blow when the set temperature is reached. This safety precaution is to keep excessive harm from your unit by the heater and is a one-time use, resulting in the replacement of the entire defrost sensor.
Defrost drain problems

1. Clogged or freezing defrost drain

If you are experiencing defrost drain issues, it is possibly due to a clogged or freezing drain that is blocking water flow to the bottom of the freezer. This will cause the defrost water to drain and drip down to the bottom of the freezer section. To correct this issue, thaw any ice or remove debris that could be causing the clogged drain or replace the drain heater.

1. Drain heater

If you are experiencing defrost drain problems, inspect the defrost drain heater. A dislocated or burnt out drain heater will result in the drain tube freezing over. Attempt to return the part to the designated position or replace the damaged part to correct the issue. Search Over 2 1 Million Appliance Parts

dont worry about it, you probably didnt get the freezer drawer closed all the way. frost will form when it doesnt get closed properly. just make sure it is closed now and the unit will clear the frost in a few days thru normal defrosting cycles. be sure that the drawer is closing on all sides by looking at the gasket and all should be ok in the future.

test this steps and fix it, use the VOM. God bless you

1. Defrost control boardIf the defrost function is not working on your refrigerator it could be an issue with the defrost control board. This control board oversees several internal conditions and regulates the activation of the defrost cycle. A faulty board can be the primary reason your refrigeration unit is not transitioning to the defrost cycle. Over time, the buildup of ice on the evaporator coil will prevent the refrigerator and freezer from maintaining proper internal temperature. It is advisable to first check the defrost heater and the defrost thermostat for continuity prior to replacing the defrost control board.
   
2. Main control boardA possible cause for a refrigerator not defrosting, especially on more modern units, is the main control board. The main control board acts as a "brain" for the unit controlling the defrost cycle, compressor, and run time, and essentially acts in place of the defrost timer. The control board can be tested using an ohm meter for functionality and will need to be replaced if bad.
   
3. Defrost timerIf the refrigerator is not defrosting the timer could be malfunctioning. Numerous times throughout the day the defrost timer should cycle the defrost heater on as a means to melt frost buildup on the evaporator coils in the freezer. If this timer does not cycle on, then it may be faulty and require replacement.
   
4. Defrost heater assemblyIf your refrigerator is not defrosting accurately this could be an indication that your defrost heater assembly has failed. This could cause the frost to accrue on the evaporator coils, eventually blocking the airflow resulting in the unit not cooling properly. The defrost heater assembly can be monitored for continuity using an ohm meter and will need to replaced if there is none present.
   
5. Defrost thermostatAnother cause of your refrigerator not defrosting is a faulty defrost thermostat. A requirement for the defrost heater to activate to melt away frost on the evaporator coils is a functional defrost thermostat. The defrost thermostat senses the temperature of the evaporator coils and initiates the thawing process by activating the defrost heater. If the thermostat is faulty, it will not sense the lowering temperature of the coils and will not turn on the heater, resulting in an advanced frost build-up. The defrost thermostat can be checked for continuity by using an ohm meter; if there is no continuity the damaged part will need to be replaced.
   
6. Defrost sensor with fuseAnother possible cause of a refrigerator that does not defrost properly is a defrost sensor with a fuse. If the defrost sensor fails, the fuse acts as a one-time-only fail safe for the sensor -- if the sensor does not shut off the defrost heater, the fuse will blow when the set temperature is reached. This safety precaution is to keep excessive harm from your unit by the heater and is a one-time use, resulting in the replacement of the entire defrost sensor.
   

Read more: http://www.appliancepartspros.com/repair-help/refrigerator-repair-help.html#9#ixzz2aX5nUL00
http://www.appliancepartspros.com

Since the defrost problem wont just go away here are details about how it works.

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.

The defrost is not working.This happens due to the evaporator coil in the inner section of freezer is got blocked by ice .--------

Try manual defrost reset procedure: ----

First unplug the unit from main power outlet. Then empty whole unit completely. Then keep both the doors open. Wait for 24 hours. All the ice collected on the coils and in the freezer section will get melted. Clean the water from the sections. Then Connect the power cord of the unit to main power outlet after 24 hours/.Then set the temperature to normal in both fridge and freezer section. It will take near to 4 hours to get run in its proper cooling cycle. Then check, if the problem returns again. If the same problem occurs then it's defrost problem. The defrost board and the defrost thermostat/heater is not functioning properly and it has to be checked and replaced.

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The procedure of this unit is as follows: --- The compressor starts then it cools the freezer section. When the freezer reaches its cooling level the defrost cycle starts functioning. In this cycle the fan in the freezer section starts running and the cool air in the freezer section is passed to the refrigerator section and the refrigerator section gets cold. The air from freezer to refrigerator passes from the section, in that section the damper is located. Now this problem which you mentioned. In this problem the freezer thaws, this happens if the thermostat is not functioning or the heater is not heating. Then the ice starts getting collected on the evaporator coil. The evaporator coil is at the internal section of freezer. If too much ice gets collected then this ice blocks the fan in the freezer section from functioning and this blocks the damper section with ice getting collected there. This all procedure is controlled by the defrost board of the unit.

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So first try reset procedure.If that is not helping then defrost assembly parts are to be checked and replaced.The defrost thermostat is located in the freezer section beside the evaporator coil.The defrost heater is located in the freezer section beside the evaporator coil.And the defrost control board is located in the fridge section.-------------

you can get the required parts from online sites like:---

www.repairclinic.com or from searspartsdirect online site.---------This will help.Thanks.Helpmech.

The unit has an automatic defrost system that defrosts the fridge automatically when frost develops or when certain conditions are met.

1. Defrosting starts when the compressor running time reaches 4 hours after a power outage or after the unit is turned on for the first time.
2. Defrosting starts each time the compressor running time reaches 7 hours.
3. Defrosting stops if the sensor temperature reaches 46.4°F(8°C) or more. If the sensor doesn’t reach 46.4°F(8°C) in
   2 hours, the defrost mode is malfunctioning.
4. Defrosting will not function if its sensor is defective or wires are cut or short circuited.

If your unit defrosts frequently even when the conditions above are not met, you have a malfunctioning sensor. You may have to ask the help of a qualified technician to disassemble and:

1. Check the connections of the sensor to the control board.
2. Inspect the wires for short or cut wire.
3. Push the reset button on the main board.
4. Replace the sensor control assembly.
   

They need air, do not cover it when in use.

If ti cools fine in summer then you just have a defrost problem.

Make sure the outdoor coil is clean.
If the coils are clean, then you have a bad defrost control.

In heat mode the unit should go into a timed or temp controlled defrost. If it is frosting up to the point of stopping the fan, in heat mode only, and otherwise operates properly, then its a bad defrost control.

It is reccomended that the defrost temp sensor be replaced at the same time the defrost control board is replaced. Some temp sensors are part of the board and not a seperate component, but not most.

I might first suspect the defrost bi-metal thermostat located in the freezer compartment behind the interior panel. It's clipped onto the coils and is usually a little round disk with a couple wires coming out of it. The reason I susupect it is that little device is what "opens" to kill power to the heater once the temps get hot enough to have finished melting the ice on the coils. If that is stuck "closed" or opens WAY out of it's heat range then the heat element will stay on way too long. Next is the actual defrost timer which can be a clock type timer or a circuit board. If you go to this site use GSS22JEM for the model number. Item 240 is the bi-metal, 241 is the thermistor sensor. http://www.partselect.com/Schematics/GE/00113124i06.gif Item 801 is the control board. http://www.partselect.com/Schematics/GE/00113123i02.gif