I'm going to try and explain this. I have my ac on and set at 72. I have a hunter programmable tstat. I live in a mobile home, I know they suck for effeciancy. The tstat is located in the hall way less than 2' away from the air return. My ac is kicking on and off about every 3 or 4 minutes. There is a temp swing going on. I take my own temperature with my own tools, I do work on hvac and know a bit about it I'm EPA certified and I have been doing it for about 2 years. Now when I take my own measurements I'll get 70 and it will shut off but the temp starts to change quickly.It will stay on till about 74 and shut off. No heat sources around. I'm thinking because it's so close to the return that once the blower shuts off that the air pulling by is cooling it off to quick and once it shuts off its messing with the tstat. Could this be the problem or just the effeciancy of my home. System works great for heat. I have a 92% goodman.