Arrived to do a performance maintenance. Set up for combustion analysis temperature split and static pressure tests. Verified operation of all mechanical and electronic components of the furnace. Found that the system is not wired for heat pump operation. Checked blower for cleanliness and to see if there is any play in the bearings. Found that the blower wheel is coated in dust debris. Checked systems heat exchanger to ensure proper venting of flue gas. Performed an electronic gas leak search. Found a fitting close to the water heater that is leaking gas. Furnace is operational at this time.