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Replacement parts for General Electric HSS22IFMBCC Refrigerator | AppliancePartsPros.com
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Ice forming on the bottom of freezer compartment and some water drip on the floor.. I believe replacing the thermostate and defrost heater kit would solve the problem? [/COLOR]
It sounds like everything is working OK just the drain may be plugged.
You could check the freezer temperature, it should be 0 to 5 degrees F.
If you had a defrost problem the unit would run all the time.

[COLOR="DarkRed"]The drain must be frozen so water doesn't run into evaporator pan.[/COLOR]
It may just be frozen but odds are is that the drain is either partially or fully plugged causing the water to back up and freeze.

I would check that it is clear.
Use a hair dryer to melt it. If plugged a turkey baster with warm water, an air compressor with low pressure or a wire can often be used to clear it.

Also check that it is not plugged with dust etc. at the drain pan end.
You might as well clean the condenser/compressor fan and the condenser coils while you are down there.

If it looks like stuff is growing in the tube I would flush it with a 10% bleach solution. This should kill the stuff and let you flush it out. You may have to do this several times, let it sit for 15 minutes or so between flushes.

Be careful that the drip tray does not overflow and empty the drip tral after you are done.

Be sure to unplug the unit while doing this.