Arrived on site to perform diagnostic on 5 year old Day N Night unit. Homeowner had the system replaced 5 years ago but can no longer get a hold of the company that installed it. He replaced his older system and also the lineset running underground because he would always have to recharge the old system until they located the leak in the lineset. Now his new system started to have trouble cooling down the home a couple weeks ago. Cycled System for cooling. Unit kicked on normally and started operating. Gauged up to system to check refrigerant pressures. Let system run for a while to get heat load. System does have a refrigerant charge, but it is definitely low on refrigerant which is causing the unit to not cool the home down. System has developed a refrigerant leak in either the indoor or outdoor coil, or the lineset. Went over findings and recommendations with homeowner, as well as possible future repairs associated with a leak once it is located. Homeowner wants to hold off on any r