Arrived to do a multi system performance maintenance. Set up for combustion analysis temperature split and static pressure tests. For each furnace. Found that the fan speeds were wrong on the new furnaces. Made the necessary changes and retested. Found that the attic system is operating with excessive static pressure. Verified operation of all mechanical and electronic components of each furnace. Checked blowers for cleanliness and to see if there is any play in the bearings. Checked each systems heat exchanger to ensure proper venting of flue gas. Performed an electronic gas leak search. Verified operation of each humidifier. Found that all panels are coated in calcium buildup, and the shutoff valve for the “kitchen” system is leaking and has been shut off. Spoke with homeowner about the each systems needs. With homeowners approval replaced the furnace filter in each system(rated for up to a year). Replaced humidifier panels in each humidifier. Replaced the leaking saddle valve with a