Originally Posted by oleesa
I was wondering if anyone could help me figure out what could be wrong with a frig. just got it from one of my friends to see if I could fix it...but it wont cool either side. Any clues!
I presume that by "either side" you mean that neither the freezer section nor the fresh food section will be cool or cold.
If you have two doors on the front of your fridge; one for the freezer and one for the fresh food section, then you have a frost free fridge.
What you need to do is look in the freezer section for a cover of some sort that can be removed. Often, the screws holding those covers in place will have plastic "buttons" over them that need to be pryed off in order to access the screw head.
Behind that cover you should find an "evaporator coil", recognizable because it looks like a coil of aluminum tubing with fins sticking out of it all over the place along it's entire length. In front or behind that evaporator will be an "evaporator fan" which looks very much like you'd expect a very simple fan to look like, and somewhere in the midst of the evaporator coil will be an electric heating coil called a "defrost heater".
Watch whats behind that cover. Your evaporator should be covered over it's WHOLE LENGTH with a coating frost when the fridge is operating. (That means that the compressor and defrost fan are both operating.) The shorter the length of the evaporator coil that's covered with frost, the weaker the charge of refrigerant in your cooling system. If your cooling system is severely depleted of refrigerant, you might just see a "snowball" forming where the refrigerant enters the evaporator coil. Hopefully it's not that bad because the cost to evacuate the cooling system, find the leak and repair it, and then refill the cooling system with new refrigerant will probably cost near as much as a new fridge would.
If the evaporator coil isn't covered with frost AT ALL, it could just be that the defrost timer is stuck in the defrost mode. The defrost timer is the "brains" (if you will) of a frost free fridge because it tells the fridge when to defrost itself. Once every day (or so) the defrost timer will divert electrical power from the fridge's compressor motor and evaporator fan and send that electrical power to the defrost heater instead. The defrost heater will get hot and it's radiant heat will melt the frost off the evaporator coil. Once all of the frost off, the subsequent rapid increase in the temperature in the area of the defrost coil will be detected by the "defrost thermostat", which is wired in series with the defrost heater. That defrost thermostat will open, breaking the circuit to the defrost heater, and thereby preventing any melting damage to the styrofoam parts in the area of the evaporator coil.
So, check the operation of both the evaporator coil and the evaporator fan. A healthy fridge will develop a uniformly thick layer of frost all along the length of the evaporator coil, and the evaporator fan will operate all the time the fridge compressor is running, and will stop when the fridge compressor stops because both are turned on and off simultaneously by the defrost timer.
The defrost timer can be located darn near anywhere in your fridge. It will have a shaft on it that will be obviously designed to be turned in one direction only with a slot screw driver cuz you can wreck the defrost timer by turning it backward. Contact the local "factory authorized service depot" of the manufacturer of your fridge to find out where the defrost timer is located on your model off fridge. Mark that defrost timer's shaft position with a felt pen or something and check it periodically over the course of a day or so to ensure that the shaft on it is turning. If it's turning, and takes the same time to rotate a full 360 degrees repeatedly, then the defrost timer is probably OK.
If the evaporator coil develops a layer of frost over it's entire length (or most of it's length), and the defrost timer turns the defrost heater on so that it gets red hot for anywhere from 10 to 30 minutes every 8 to 20 hours or so, and if the evaporator fan turns on with the compressor and blows cold air into the freezer section of the fridge so that you can feel a bit of a draft in there and turns off with the compressor too, then the only remaining possibility is that the fridge thermostat (called "cold control") is busted.
I have a blurb on my hard drive explaining how the defrost system on a frost free fridge works. If you request it, I will post it in this thread for you to read.