-Performed CMA Inspection on 4 split system heat pumps. Verified operation of 3 exhaust fans and 3 gas heaters. -Split System 2: Observed audible buzzing sound at air handler disconnect when engaging condenser from air handler. System may be in need of electrical inspection/diagnosis. System operates as expected. -Split System 4: System is over 25 years old, uses R22 refrigerant and was found to have an evaporator coil in poor condition previously. Customer has been advised to consider replacing system. System services unoccupied space and is currently not in use. -All equipment operating properly at this time.