Complete 1 system furnace repair and preventative maintenance check. Change 16x25x1 filter, open return in the bedroom to help reduce noise. Find a 15-year-old heating system operating with high co level, worn flame sensor, worn ignition, and weak blower motor capacitor. Compressor combustion calibration service and reduce co level. Replace the blower capacitor. System operating at this. Need to keep a check on ignition and flame sensor. Suggest cci plan and suggest water protection for the system in the attic.