Hello all! I have been in the HVAC field part-time for nearly 20 years, but I am having a problem with one of my refrigerators that has me stumped. It is a cheapo top-freezer fridge labeled as an RCA. It uses R-134a with a forced condenser underneath and a forced spine and tube evaporator mounted flat against the back of the freezer with the fan above it. The problem is a sort of ticking that is coming from the back right area of the evaporator where the refrigerant lines enter and exit the coil. The ticking happens at a rate of about 3 per second. It doesn't seem to happen at all when the refrigeration cycle first starts but starts about 50% of the way through a cycle. It almost sounds like a slight water hammer would sound in a steam heating system. I suspect it is refrigerant causing the sound. It is fairly loud and has been happening (as far as I know) since the fridge was new. Since the noise starts when the compressor has been running for a while it leads me to believe that the sound doesn't happen when the evaporator pressure is high and starts to occur when the pressure starts to drop through a cycle. It will also stop within a few seconds whenever you open the freezer door. When I pulled the evaporator cover panel I noticed that the cap tube enters from the top of the freezer and is soldered into the larger evaporator tubing then it immediately turns 90 degrees to the right. This elbow was sagging creating a little trap, so I straightened it out a little so that it sloped down towards the evaporator. Once assembled and tested the sound was worse. I took it down again and moved it back to the original position and the sound is reduced to where it was before. Anybody got any ideas? It is driving me nuts.