Arrived to do a dual system performance maintenance. Set each system to heating and created a call for heat. Tested ignition and proving components of the furnace. Tested limits pertaining to flame rollout and system air temperature. Measured a temperature split between return and supply air. Measured power consumption of each inducer and blower motors. Found that the fan in each system is drawing more amps than they are rated for. Shut systems down and inspected the interior of each system. Found bacterial growth present on the evaporator for the right hand system. Spoke with homeowner about the systems. Heating and cooling systems are operational upon departure.