Why Your San Antonio AC Freezes Up in July (and How to Stop It)

By Manny Pozos · June 29, 2026 · 4 min read

It's one of the most common calls we get in July: the AC is running non-stop, the vents are blowing warm, and there's a block of ice on the copper line outside. I'll give you the honest version of what's happening.

It's almost always one of two things

A frozen coil means your evaporator got colder than it should and condensation turned to ice. In San Antonio that usually comes down to restricted airflow (a dirty filter, closed vents, or a failing blower) or low refrigerant from a leak. Both are fixable — but only one is cheap.

What you can do right now

Turn the system to OFF and the fan to ON for an hour or two to melt the ice, then replace your air filter. If it freezes again within a day, that's a real diagnosis, not a guess.

Why we don't just "add a pound of freon"

Topping off refrigerant on a system that's low means it's leaking — and a top-off just delays the real repair. We find the leak, weigh in the correct charge, and tell you the honest repair-vs-replace math. That starts with our flat $85 diagnostic, credited to the repair.

Want the full, step-by-step breakdown? Read our Learning Center guide: Why Your AC Freezes Up or Won't Cool, or call us at (210) 535-1515 for same-day service.