STRANGE REFRIGERATOR NOISES
Actually, there aren’t too many things in a fridge that can cause a lot of noise. A few that you might commonly hear are:
A rattling or a buzzing noise might be coming from the evaporator fan or condenser fan hitting something.
It may also be that the outside defrost drain pan or compressor mounts are loose and something is vibrating a bit.
You need to pull the refrigerator away from the wall and poke around the compressor and condenser fan, and see if the rattling stops.
If it seems to be coming from inside the freezer section, it may be the evaporator fan. Sometimes the fan stops when you open the door, so open the door and press the door switch to turn the fan on. If you think it’s coming from the evaporator fan, CLICK HERE.
A whistling or warbling sound usually is coming from the evaporator fan motor. Replace as described HERE.
A hissing or gurgling sound might happen for a few minutes after the compressor shuts off. This is the Freon flowing through the tubing in the system. When the pressure throughout the system equalizes, the noise will stop. If there is no evaporator fan running, you may hear the Freon gurgling through the evaporator at any time the compressor is running, and for a few minutes afterwards.
A hissing sound can also come from the defrost system when it is in defrost mode. Ice melts from the evaporator, and the melt water hits the defrost heater. It instantly boils, and makes popping and hissing sounds. The sound will stop when the refrigerator stops defrost and starts cooling again.