Why is my AC freezing up?

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First — turn it off

If you see ice on the refrigerant lines or the indoor coil, switch the system to OFF (or fan-only) right away. Running a frozen AC forces liquid refrigerant back to the compressor — the most expensive part in the system — and can destroy it. Let it thaw fully (a few hours) before doing anything else.

The two big causes: airflow and refrigerant

An AC coil freezes when it gets too cold, and that happens for one of two reasons: not enough warm air moving across the coil (an airflow problem) or low refrigerant (usually a leak). Almost every frozen-AC call comes down to one of these.

Airflow problems you can check yourself

Start with the easy stuff: a dirty filter is the number-one cause — replace it if it’s gray. Make sure plenty of supply vents are open and not blocked by furniture or rugs, and that the return grille isn’t covered. If the filter and vents are fine but it still freezes, the restriction is usually deeper — a dirty blower wheel or indoor coil — which needs a tech to clean.

Refrigerant: why “just add some” is the wrong fix

If airflow is good and it still ices up, you’re likely low on refrigerant from a leak. Refrigerant doesn’t get used up — if it’s low, it’s leaking out. Topping it off without finding the leak just freezes again in a few weeks and wastes your money. The right fix is to find and repair the leak, then weigh in the correct charge. That’s how we handle every AC repair.

How to get it cooling again

If a new filter and open vents don’t solve it, it’s time for a pro — a frozen coil that keeps coming back is telling you something. We’ll diagnose the real cause, show you what we find, and quote the fix upfront. We offer same-day and after-hours service across the Salt Lake Valley.