Maintenance
A Year-Round HVAC Maintenance Plan for a Busy Household
Put four dates on the calendar, and keep a filter you can actually reach. Most no-heat and no-cool calls in a lived-in house start with a skipped filter, or with a system nobody turned on until the day they needed it.
Winter
If you heat with a furnace, this is when it fails, not when you should look at it for the first time. Listen for a new rattle, a burner smell that is sharper than last year, or a room that used to keep up and now does not. Change the filter if December got away from you.
On a system older than about ten years, book a combustion check before the next hard cold snap if you have not had one. If someone suspects a cracked heat exchanger, leave the furnace off until it is checked.
Spring
On a mild day, set the thermostat to cool and let it run for ten minutes. You want the outdoor unit to start, the indoor fan to blow, and water to leave the condensate line. Then shut it off.
Clear a two-foot ring around the outdoor unit. Cottonwood, grass clippings, and last year's leaves pack the fins. The system then runs longer for the same temperature. This is also the right month for a cooling tune-up, before the first hot week, not during it.
Summer
Filters load faster when the air conditioner runs all day and people are home with pets. A one-inch filter in a busy house is often finished in 30 to 45 days, not 90. If the supply air feels weak, check the filter before you assume the blower died.
Leave the fan setting on Auto unless someone in the house needs the air moving. On keeps the blower stirring dust onto a wet coil.
Fall
Run the heat for ten minutes before the first cold night. If you have a gas furnace, make sure nothing is stacked against the flue. If you have a heat pump, make sure the outdoor unit is not sitting in leaves. This is the sensible time for a heating tune-up.
What you can skip
A new thermostat every year, a UV light from a flyer, and a maintenance club that exists to sell a replacement are easy to skip. Changing the filter on time and getting one real inspection a year stops most of the emergency calls.