An outdoor central air conditioning unit mounted on a concrete pad beside a blue-sided house at sunset.

AC Maintenance in St. Louis, MO

Air conditioners here run from May through September, so April is the time for a tune-up. Tell us about your system, and a licensed contractor who covers St. Louis will get in touch.

Tell us about the job

It takes about a minute.

Step 1 of 3: Equipment

What kind of equipment?*

An outdoor air conditioning condenser unit positioned beside a blue-sided house at sunset.

Five months of St. Louis heat adds up fast

Your air conditioner runs from May through September here, and on a lot of those afternoons it's pushing against 87 degrees to keep the house comfortable. That is five straight months where the compressor and fan barely get a rest.

St. Louis has also seen 16 hail events and 28 damaging wind events over the last ten years, with hail up to 2 inches across. That kind of weather can bend the fins on your outdoor unit or knock its coil out of alignment without you ever noticing from inside. A tune-up checks the coil, the refrigerant charge, and the electrical connections before a hot stretch finds the weak point for you.

5 months: May through September, your air conditioner is on duty
87°F: the average summer afternoon it cools against
16 hail events: in ten years, and hail bends the fins on outdoor coils
28 wind events: in ten years, and wind drives debris into outdoor units

Isometric cutaway illustration of a house interior showing ducted air handling equipment and duct runs through rooms, connected by piping to an outdoor condenser unit on a pad outside the wall.

Your air conditioner works hardest from June through August.

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NOAA nClimDiv, 1991–2020 normals

Overhead view of a gray residential air conditioning condenser unit mounted on a concrete pad beside a house with asphalt shingle roofing.

Book your AC tune-up in April, before homes here start needing cooling in May.

A tune-up checks the refrigerant charge, cleans the coils, tests the capacitor and tightens the electrical connections.

What does AC maintenance include?: A technician checks refrigerant charge, cleans the condenser coil, and tests the capacitor and contactor. They also check the blower motor, inspect the ductwork connections, and change or check the filter. They check the condensate drain too, since a clogged one can shut the system down or cause water damage inside the house.
How often does an air conditioner need maintenance?: Once a year, ideally before the season starts. Homes here run the AC from May through September, five months of steady work, so a spring checkup catches problems before the first hot week hits. A unit that sat idle since fall can have a weak capacitor or a dirty coil that only shows itself once it is running hard.
Is AC maintenance worth it?: Yes. Summer afternoons here average 87°F, and the system runs at that load for five months straight, so a weak part gets found on a checkup instead of on the afternoon it fails. Maintenance also keeps the coil clean and the refrigerant charge correct, both of which affect how well the unit cools the house and how long it lasts.

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