Came out to call for the furnace not heating properly. Customer was due a service as well, but the maintenance plan had expired. Customer stated that the system wasn’t reaching temperature in the home and was staying at about 69 degrees and the thermostat was set to 72. I inspected the furnace over and found it to be operational at the time of inspection. I did, however, find the filters dirty and needing to be changed. I discussed with customer about what I found, and that the system was most likely having trouble keeping up due to the dirty filters. I replaced filters for customer and performed a maintenance on the furnace. Inspected blower assembly, blower motor, electrical components, heat exchanger, burners, flame sensor, ignitor, gas valve, inducer motor, and pressure switches. I cleaned the flame sensor and brushed dust off the burners. Cycled furnace on and checked amps, temperatures and pressures of gas. System is heating properly. Seeing that the customer had a service owed