Got a 9yr old w/house fridge/freezer model BJ504Q. Had the defrost heater element replaced 4 weeks ago While the heater works it is not it is not defrosting the upper part of the element which is still freezing up, causing lack of proper cooling in both sections. Any Ideas Thanks Ray

check and test evap fan if not up to rmps will allow icing

If the timer didn't fix your problem, and it sounds like it didn't, then there are 2 other components to a defrost system. The defrost heater, and the defrost thermostat. Both are located around evaporator. Back inside wall of freezer will have to be removed to access these parts. Thermostat will be clipped near top of evaporator coil. Heater will be near bottom of coil.

The frig has a defrost timer which activates an electric element which cyclially defrosts the evaporator in the freezer.If either the heating element or the defrost thermostat are faulty the freezer evaporator will freeze solid not allowing cold air circulation to the rest of the frig.
At a suiteable time empty fridge contents into insulated containers and turn fridge off at powerpoint and allow to fully defrost leaving doors open.The evaporator coil in frostfree is normally located behind the rear panel of the freezer.If you do not have defrost heater it will take 3-4 hrs for complete defrost.
After defrost turn fridge back on and make sure items to be returned to freezer are free from moisture and ice and keep freezer open for minimum of time as moisture will start building up onthe evapoator.
If the fridge works ok for a couple of days and the the original problem returns the problem is with defrost thermostat or defrost heater

You have a problem with the defrost system. There 3 components... heater, thermostat, and timer or adaptive defrost control depending how old your refrig is. Check heater and thermostat( located on the evapotator coils) with an ohm meter. The heater will have some resistance and the thermostat will be closed(must be cold). If these check good replace timer or adaptive control.

The fridge gets its cold air from the freezer through a vent(damper) between the freezer and fridge.The fan in the freezer blows air through it. There is a flap you adjust with the fridge temp. control. Make sure it's opening and closing when you adjust the fridge temp .

OR.
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.

Because it is still running I believe the defrost heater may have burned out. The part number for the heater is WR51X10055 You will need to unplug and remove the rear panel in the back of the freezer to confirm. It will be easy to spot if burned out because it has a glass tube around the element. If you replace the defrost heater I recommend you also replace the defrost thermostat. If the evaporator is frozen over you may need to defrost with a hair dryer to be able to see anything . Sea Breeze

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

In my GE side-by-side there is a defrost temp sensor located near the top of the evaporator coil. I think the control board uses that temp sensor to know when it should be done defrosting.

On the schematic of my fridge (link below), the defrost thermistor is part number 240 in the diagram (not part number 241, which is a different temp sensor located adjacent to the one you want)

http://www.partselect.com/ModelFrames.aspx?ModelID=361233&ModelNum=GSS20IEMDWW&mfgModelNum=&ManufactureID=2&Selected=00113321i06&Position=2&mfg=GE&Type=&Mark=2

I don't know why the defrost element would fail immediately other than incorrect supply voltage or just a bad defrost element.

Generally on these models they rely on cold air being pumped fr\om the freezer to the fridge and have a adjusting device to control the flow, you need to locate and check this is free and working properly. Another reason for freezer ice up is a shortage of gas in the unit, this is usually unfixable as the leak can rarely be found as it usually occurs within the cabinet case. Sorry to say it would then be a throw away.

Peter

The most common cause of this with a GE fridge is the defrost heating element is burned out.
Empty the freezer, take out the shelves and remove the back wall. You will see the heater at the bottom of the evaporator coil. It is a glass tube with a heating element inside it. Some models have two heaters, some have one. If either one looks black inside the glass it is probably burned out. You can check them with an ohm meter. If you don't have a meter, take the heater to an appliance parts dealer and they will check it for you. If yours has two heaters, they must be replaced as a set.
If the heater is not your problem, post the complete model number from the fridge and I will try to walk you through the defrost system checks.
Mike