Maintenance

How Often to Service a Furnace and AC in a Hot, Humid Climate

In a dry climate, one visit a year is usually enough. Where the air conditioner runs from April into October, and the outdoor air stays muggy for weeks, that visit should land before cooling season. Waiting until the first 95-degree week means you are booking a repair, not maintenance.

Air conditioner

Have it serviced once in early spring, every year. On a system older than about eight or nine years that ran hard all summer, a second look in late summer is reasonable. On that visit they should be looking at the coil, the drain, and the capacitor, not walking you through a new system.

Furnace or air handler

Once in the fall. Along the Gulf Coast and in south Texas and Florida the heating season is short, but the air handler still sits in a wet cabinet. That cabinet is where drains clog and where a blower wheel packs with dirt. Heat strips and gas burners still need a look even if they rarely run.

Heat pump

Treat it as the cooling machine it mostly is. Service it before summer. In the fall, confirm that defrost works and that backup heat comes on when it should, even if you almost never need it. Backup electric heat is what shows up on the bill when the outdoor unit starts to fail quietly.

Refrigerant is not a yearly item

A sealed system does not use up refrigerant the way a car uses oil. If the charge is low, there is a leak. A shop that adds refrigerant every spring and never looks for the leak is selling the same repair twice.

Filters need more attention than the package suggests. A loaded filter drops airflow across a cold coil. The coil stays wet, supply vents start to smell, and the house never quite catches up. From May through September, check a one-inch filter every month. Which filter to buy depends on the size printed on the one you pull out.