Performed semiannual maintenance on two heat pump heating systems. Inspected all Performance, Mechanical and Safety Systems. Attic HVAC System: On the indoor air handler that is located in the attic, I found lots of oil residue on the coil piping. I used my electronic leak detector and soap bubble leak detection solution and found a leak along the coil piping. I also checked the refrigerant charge of the R-22 system and found it to be low Entry Way Closet HVAC System: I flushed and treated the primary drain line and verified all buildup and gunk exited the outside drain exit next to the condensing unit. Also verified the system was operating within manufacture’s specifications for operation. Everything is working at this time.