500 sq.ft. apartment, 2nd floor, 32 y.o. through the wall, ducted air heat pump. The pump is installed in a closet next to the apartment (separate entry), and the air ducts spread from there along the front of the condo unit to 5 openings. It heats well, cools not so well: when the inside of the apartment heats to 79 during the day, it can bring it down to about 70; but the outside temperature is about 70 as well, so just a window fan would have helped as much.
I found that:
- Some of the ducts have leaks
- Air leaks out of the unit
- Some of the duct insulation is off, exposing ducts to the temperature in the HVAC closet.
- Coils seem to be relatively cold to touch after 15 mins of operation
R12 is used as a refrigerant.
I appreciate starting points as to how to troubleshoot the problem.