Last reviewed: August 20, 2026. This guide reflects federal information available on that date. State, Tribal, utility, building-code, and program rules can differ by location.
Maintenance is usually cheaper than emergency repair, but a useful calendar must adapt to local weather. Move each task earlier when hurricane, wildfire, heating, cooling, or freeze season arrives sooner in your area.
Every month or during heavy-use periods
- Check the HVAC filter. Replace or clean it according to the equipment and filter manufacturer. Construction dust, pets, wildfire smoke, and long run times can shorten the interval. A higher-efficiency filter is useful only if the system can handle its airflow resistance.
- Review energy use. Compare the bill with the same month last year while noting weather, rates, occupancy, thermostat settings, and electric-vehicle charging. A sudden unexplained change can reveal a stuck auxiliary heater, failed water heater, duct problem, or billing issue.
- Look and smell for water. Check under sinks, around toilets and water heaters, below roof penetrations, near condensate equipment, and at basement or crawl-space walls. EPA advises drying wet materials within 24 to 48 hours when possible to reduce mold risk.
- Keep vents clear. Do not block supply or return grilles with furniture. Check that exterior exhaust terminations are unobstructed.
Before cooling season
- Schedule service if the manufacturer calls for it or if the system had poor cooling, unusual noise, ice, high bills, or drainage problems last year.
- Remove leaves and debris that obstruct the outdoor unit while protecting coil fins and required clearances.
- Inspect the condensate pan and drain. A blocked drain can cause water damage and shut down equipment.
- Check window screens, operable windows, exterior shading, and weatherstripping. Use outdoor air for cooling only when temperature, humidity, pollen, and smoke conditions are suitable.
- Test the thermostat and confirm the schedule reflects current occupancy.
DOE states that routinely replacing or cleaning air-conditioner filters can lower the unit’s energy consumption by 5% to 15%. Treat that as a general range, not a guaranteed bill reduction.
Before heating season
- Have fuel-burning equipment and venting inspected as required. Soot, flame changes, odors, or alarm activation require prompt professional attention.
- Test smoke and carbon-monoxide alarms using manufacturer instructions and replace devices or batteries on their specified schedule.
- Inspect attic penetrations and the attic hatch for air leakage, but maintain required clearances around flues, chimneys, and heat-producing fixtures.
- Protect vulnerable pipes and outdoor faucets before freezing weather. Know the main water shutoff location.
- For a heat pump, learn what the thermostat’s auxiliary or emergency heat indicators mean. Unexpected prolonged auxiliary-heat operation can raise consumption.
Spring water and exterior check
- Inspect roof coverings from a safe location and arrange professional evaluation for missing materials, storm damage, or failed flashing.
- Clean gutters and confirm downspouts discharge where water flows away from the foundation. EPA specifically recommends maintaining gutters and grading away from the building as mold-prevention measures.
- Check siding, penetrations, exterior sealants, decks, and foundation cracks. Sealant is not a substitute for correct flashing.
- Check sump pumps and approved backup systems before storm season. Never enter a wet area with energized equipment.
Fall drainage and enclosure check
- Clear leaves from roof drainage, areaways, outdoor drains, and heat-pump or air-conditioner surroundings.
- Inspect door sweeps and operable-window seals. Repair the source of rot or moisture before cosmetic work.
- Examine accessible duct connections and insulation. Do not use ordinary cloth “duct tape” as a permanent duct-sealing method.
- Confirm bathroom and kitchen exhaust works and terminates outdoors.
Once a year
Review insurance limits and the home inventory; check appliance hoses; flush or service the water heater only as the manufacturer directs; inspect dryer exhaust; check attic and crawl-space moisture; and review the household outage plan. Record model and serial numbers, filter sizes, service dates, and shutoff locations in one place.
Tasks to leave to professionals
Refrigerant work, electrical-panel work, combustion testing, chimney repair, structural roof work, contaminated flood cleanup, extensive mold remediation, and work near suspected asbestos or lead require appropriate training. Maintenance should reduce risk, not create a new exposure.
This article provides general educational information, not tax, legal, engineering, or medical advice. Use licensed professionals where permits, combustion equipment, refrigerants, structural work, electricity, or contaminated water are involved.