July 10th, 2012
Your refrigerator is doing its job well EXCEPT that there’s water showing up on the floor, and if you inspect the freezer compartment, you see that there’s a pool of frozen water on the bottom of the freezer.
The chances are good that your defrost drain is plugged up with ICE, and the defrost system is working correctly.
(If water is appearing on the floor, but you’re sure its not coming from inside the box there’s another problem going on which I’ll touch on in a later post.)
So I’ll go through a defrost cycle in a nutshell:
Every 8- 10 hours of accumulated compressor run time, the system automatically goes into a defrost cycle- to melt the accumulated ice off the evaporator coils. In this mode, a heating element- just below the evaporator coil, is energized and heats up, whose purpose is to melt the ice off the coil.
The melted ice, drips from the evap, and collects into a trough just below, where the water then flows into a drain tube that deposits the water into a catch pan next to the compressor. The heat of the compressor evaporates the water and the cycle repeats itself every 8- 10 hours.
Why the water then?
Well, many defrost drains (especially as the ref gets older) will slowly begin to constrict with a thin layer of ice over time. The insulation surrounding the defrost drain port gets inundated with water and doesn’t insulate the port very well any longer. So it allows water to freeze more easily around the port’s edges until it gradually ices over the port completely. From that point on, each subsequent defrost cycle begins to collect water above the drain, till it overflows the trough, and spills onto the floor of the freezer, and then ultimately out the box and onto the floor.
So what to do?
Well, something must be employed to prevent the defrost drain from icing over. There are a couple ways. One is to loop a piece of dead soft wire around the heating element a few times and then drop the ends of the wire into the defrost drain port. When the heater energizes, the wire is heated with it, and the drain remains warmer. Or, we can install a low wattage electric heater, and place it into the drain. Either way works pretty well and it will end the water leaky situation for good!
Now, if you should notice water on the floor and you’re quite certain its not coming from inside the box, the likely cause will be a plastic water line that leaks (mice chewing through it maybe), a cracked water valve or a defrost catch pan that is cracked and leaking.
Helpful? Let us know!