Seasonal HVAC care

Spring is for cooling: replace the filter, clear leaves and debris from the outdoor condenser, confirm two feet of clearance around it, check the condensate drain runs freely, and run the system for a full cycle on a mild day to make sure it actually cools before you need it to.

Fall is for heating: replace the filter again, test the thermostat's heat mode early, listen for anything unusual on first firing, and — critically — test your carbon monoxide alarms and replace their batteries if you have any combustion appliance. That last item is not optional.

The financial argument for shoulder seasons is simple: contractors are less booked, and you find the failed part in October rather than during the first hard freeze when everyone is calling at once.

How to choose

Book spring cooling service in early spring

Not in the first heat wave. Availability collapses the week temperatures spike.

Test heat before you need it

Run the furnace for a cycle on a cool fall day. A failure discovered in October is a scheduling problem; in January it's an emergency.

Test CO alarms every fall

Any home with a gas, oil or propane appliance needs working carbon monoxide alarms. Replace batteries and check the unit's own expiration date.

Clear the outdoor unit both seasons

Leaves in fall, cottonwood and grass clippings in spring. Restricted airflow costs efficiency and stresses the compressor.

Change the filter at the season change

Carrier's baseline is at least every other month; tying at least two changes to the seasonal switch makes it easy to remember.