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- Cycle check
Time one cooling cycle
Start the stopwatch when the outdoor unit kicks on and stop it when it shuts off. How long that takes says a lot about sizing, airflow and refrigerant — and it costs nothing to find out.
Cycle length
0:00Do it on a hot afternoon with doors and windows shut. One cycle is enough.
Start the clock
When the cycle ends, this panel explains what that length usually means — and what we would check next.
- Under 7 minShort cycling. Common causes: an oversized system, a dirty filter or coil, low refrigerant, or a thermostat in a bad spot.
- 7–15 minNormal on a mild day. On a 95°F afternoon it is on the short side — worth a look.
- 15–40 minWhat a properly sized system usually does when it is hot. Long, steady runs remove humidity.
- Over 40 minFine on the hottest days. If it happens on mild days, check airflow, refrigerant charge, duct leaks and insulation.
Why cycle length matters here
On the Gulf Coast side of Texas, comfort is as much about humidity as temperature. An air conditioner only pulls moisture out of the air while it runs, so a system that blasts cold air for three minutes and stops leaves the house cold and clammy.
Bigger is not better. A system with more capacity than the house needs reaches the thermostat's number quickly, shuts off, and never runs long enough to dry the air.
What we check after a short cycle
- Filter and indoor coil — the cheapest causes first
- Airflow at the registers and static pressure across the system
- Refrigerant charge and superheat
- Where the thermostat sits and what it can feel
- Capacity against a room-by-room load calculation before any replacement
