HVAC systems fail at the worst possible time: the first hot week or the first cold snap. A simple maintenance routine catches most avoidable problems before they become emergency calls.
Monthly checks
Change or clean the air filter according to the manufacturer and your household conditions. Pets, dust, and high usage shorten the interval. A clogged filter restricts airflow and makes the system work harder.
Look at the outdoor unit for debris, blocked airflow, or obvious damage. Keep the area around it clear. Check the condensate drain line for clogs or standing water.
Before heating and cooling season
Before summer, test the AC on a mild day and listen for unusual sounds. Before winter, test the furnace and check that the thermostat switches between modes correctly. Replace batteries in battery-powered thermostats and check the schedule.
Walk around the house and check vents for blockage. Make sure furniture and rugs are not covering returns. If the system has a humidifier or dehumidifier, follow the manufacturer's seasonal maintenance steps.
Annual professional service
A professional tune-up typically includes checking refrigerant levels, electrical connections, motors, belts, burners, and safety controls. It is also a chance to measure airflow and look for duct problems.
Ask for a written summary of what was checked and any recommended repairs. A good technician will explain what is urgent, what can wait, and what is optional.
Signs you should not wait
- Repeated breaker trips or a system that will not start.
- Burning smells, loud banging, or hissing sounds.
- Warm air from vents in cooling mode or cold air in heating mode.
- Water leaking from the indoor unit.
- Carbon monoxide alarms or any suspicion of a gas leak.
For gas smells or carbon monoxide alarms, leave the building and call the utility or emergency services. Do not wait for a routine appointment.
Frequently asked questions
How often should I replace the HVAC filter?
Check it monthly and replace it when dirty. The interval depends on the filter type, pets, dust, and usage.
Is a maintenance plan worth it?
A plan can make seasonal service easier and may include priority scheduling. Compare the included services and exclusions before signing.
Why is my system running but not heating or cooling?
Common causes include airflow restriction, low refrigerant, a failed component, or a thermostat issue. A technician can diagnose it.
Need help now? Call (877) 471-2907 and describe the situation. The line is answered 24 hours a day.
About this guide: This information is general and educational. It is not a substitute for an on-site assessment, a licensed professional's advice, or your local building code. Verify licensing and insurance directly with any provider you hire.