The answer to 'how to maintain furnace' is to perform regular maintenance tasks to ensure your furnace is operating efficiently and safely. This includes cleaning or replacing the air filter, inspecting and cleaning the blower, checking the thermostat, and scheduling annual professional tune-ups.
Start by checking the air filter every 1-3 months and replacing it when it looks dirty. Dirty filters restrict airflow and make your furnace work harder. Next, use a vacuum hose attachment to gently clean the blower fan and motor to remove any dust or debris buildup. Inspect the thermostat to make sure it's working properly and the temperature settings are accurate. Finally, schedule an annual professional tune-up with a licensed HVAC technician to thoroughly inspect, clean, and service your furnace.