I have a fridgidair #FGHB2869LP4 and it had been collecting ice in the back and i had a repair man come today. He wasn't sure how to fix this model and didn't want to get into it before reading up. Al

I would suspect the defrost timer is the problem. Go to the www.repairclinic.com for parts and repair help.

Faulty defrost I suspect. Could be thermo sensing transducer . Hard to fix as you need to almost defrost fridge before repair man arrives so he can test this transducer works properly when it is cold.

NOT SURE BUT ON MOST THERE IS A RESET BUTTON LOCATED ON THE CONTROL BOARD ITSELF.

AT TIMES The fan usually stops working due to ice obstruction when the defrost terminator has gone out and u get ice build up? u can check the terminator with a multi meter for continuity but do not check at room temperature. stick the terminator in cup of ice water for 20 minutes then check it for continuity, should be closed when cold and open at room temperature.
May also need to check the defrost timer, u can get by and test manually by placing a small screw driver into the tiny slot or hole underneath the timer and turn slowly clockwise till u hear 1 click. this will engage ur defrost cycle in about 15 minutes u should be able to come back and feel the heat in freezer as it melts the ice providing ur terminator is not bad?
Another way to test it is with a multi meter. Remove timer it from fridge and you will see 4 prongs numbered 2,1,4,3 in that order. Place ur meter prong on prong 1 & 3 (if your fridge has a capacitor wired in series with the windings, then u check for micro fares rather than OHMS) If u cannot confirm this test, still try the next.
Take ur meter prong and connect to prong 1 & 4, it should read resistance or ohms ( closed) now remove prongs and place on prong 1 & 2, this should now read infinity or open (no ohms) now take a small screwdriver place it in the tiny hole or slot under the timer. Turn it clockwise slowly till u hear 1 click. Now ur 1& 2 should read closed ( showing ohms or resistance) now place meter prongs on 1 & 4 and you it should now show open ( or no resistance - no ohms) this is how u know ur timer is good, Remember when testing for ohms ADJUST meter to use a high ohms rating in the thousands as the resistance is very high in OHMS. And adjusting to low ohms rating may give a false reading or not show the proper resistance..

Another item to check with a meter is the heating element itself. Located under the evaporator coils. It should show continuity or resistance OHMS WHEN TESTED AT BOTH ENDS OF THE PRONGS .

Lastly check the cold control thermostat with a meter for both OHMS and volts ( VOLTS is a live test with fridge plugged in so be careful) It must show 110 volts. An open or thermostat that reads infinity will not allow the proper cooling and defrosting cycles to operate and may in fact stop anything from happening as if there is no power to the unit?

ALSO CHECK THE AIR FLOW VENT SYSTEM

check and make sure your fan is working, if it is ,, it could be one of the following, adaptive defrost timer, tells it when to defrost,, defrost heater,, melts the ice,,, or the defrost thermostat,, all parts can be found on repair clinic the only way you can check the derost timer is listen and see if it shuts off,, the heater you can check with a ohm meter,,

There are a few reasons for frost building up inside the freezer compartment. Refrigerators work like dehumidifiers collecting the moisture in the air inside and defrost is supposed to remove the moisture while defrost through a drain and then to the defrost condensate pan below the refrigerator. Ever notice how ice in freezer over time the ice cubes become smaller? Or food that is not sealed dries out. You either have one of three problems. Defrost drain blocked behind the rear wall in back of freezer, air leaking into freezer through the door seal and in your case the drawer seal and finally water possibly leaking into freezer from Ice Maker, Let me know, Thanks Sea Breeze

unit may need new defrost mechanism or defrost heaters.

First I will need a model number for your Fridgidair.

Refrigerator not cooling, ice forming on back of side-by-side freezer:
Turn off unit. Empty freezer section. Remove freezer back panel (4 screws) to expose iced-over coils. Use a fan to speed up defrosting. Put a towel or a plastic drip pan in the bottom of the freezer to collect melting water (rather than letting the water collect and maybe overflowing in the drip pan underneath the refrigerator).
After defrosting, by temporarily replacing the freezer back panel and turning on the unit, the refrigerator may operate OK for about 3 weeks before the next excessive ice build up.
Possible problem- a burned out Defrost Heater.
To check: After defrosting, turn off power to or unplug the refrigerator.
Unscrew the Defrost Heater bracket (2 screws). When loose, unplug the two wires connected to the unit. Have the unit checked, or use an ohm-meter to check continuity. If unit measures "open", high resistance, replace the Defrost Heater and bracket. If the heating element shows continuity (or low resistance) the heater is probably OK and you have another problem. Now you may need to contact a repair man.

The defrost drain is frozen, you need to take the cover off inside the freezer and there will be a drain hole probably coverd with ice, you will need to pop most of the ice out first then I use a turkey baster and a tub of hot water. Squirt the hot water in the hole over and over again untill it drains. Then just wipe everything down. Problem solved.