Customer states that the heat goes out randomly and they have to reset the system entirely for it to come back on. Ran system in heating but is too warm today to be able to diagnose much. Ran in cooling and found that the superheat and sub cooling were both very low. Opened the system and found that the 2.5 to system has a .074 piston in the coil need to change out to a .061 piston. Will need to return with correct part to do repairs. Requesting to come back on a cooler day to properly diagnose heating issues.