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Find your model number - AppliancePartsPros.comIt sounds like you have a drain problem.
The water created by the defrost cycle is not draining down the drain tube into the drip tray under the unit.
I would check that the drain tube is clear.
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 tray after you are done.
Be sure to unplug the unit while doing this.
Also check that the path the water takes from the evaporator coils to the drain is clean. Anything that slows down the draining will cause a ice build up until finally the drain clogs. A light coating of buffed up wax can sometimes help the water drain quicker.
If none of the above help then there is a jiggery pokery fix that adds a drain heater to the drain but this depends on the model.
