Seasonal HVAC Maintenance Checklist for Homeowners

Monthly

Small habits prevent most breakdowns.

• Check the filter; replace when gray or every 1–3 months
• Keep vents and returns unblocked
• Listen for new noises

Spring (cooling)

Before heavy AC use.

• Clear 2 feet around the outdoor unit
• Check the condensate drain flows
• Professional tune-up: coil cleaning, electrical tests, refrigerant check

Fall (heating)

Before the first cold night.

• Test carbon monoxide alarms
• Clear outdoor furnace vents
• Professional tune-up: combustion test, flame sensor, igniter, heat exchanger inspection

How often to change the air filter

Filter life depends on the filter type, pets, construction dust and how much the system runs. A 1-inch filter in a busy summer may need changing monthly; a 4- or 5-inch media filter often lasts 6 to 12 months. When the filter looks gray or you can see dust built up on the intake side, replace it regardless of the calendar.

• 1-inch pleated filter: every 1–3 months
• 4–5 inch media filter: every 6–12 months
• Homes with pets, smokers or renovation dust: check monthly
• Wildfire smoke events: check after each event

Heat pumps and dual-fuel systems

A heat pump heats and cools with the same outdoor unit, so it works twice as many months as an air conditioner. That is why many technicians recommend two visits a year: one before cooling season and one before heating season. In snowy areas, keep the outdoor unit clear and make sure it can drain during defrost.

What to write down after each visit

Ask the technician for the readings, not just a sticker. Comparing numbers year to year shows when a part is weakening before it fails.

• Capacitor values compared with the rated value
• Temperature split across the indoor coil
• Refrigerant pressures and superheat or subcooling
• Static pressure and filter size
• Combustion readings on gas furnaces and boilers