Arrived to do a performance maintenance. Set system for cooling. Measured the systems static pressure and measured a temperature split between return and supply air. Found that the system is not moving enough air to match the tonnage outside. Adjusted the fan speed closer to spec to allow the system to operate properly, but not so high that the static pressure will cause issue. Checked interior of the furnace for cleanliness. Went outside and verified refrigerant levels. Calibrated the refrigerant levels to meet the new airspeed. Verified operation of all electronic and mechanical components. Rinsed coil free of debris. Spoke with homeowner about the system. Air conditioning system is operational at this time.