A clear guide to why central AC may stop cooling, what repairs commonly cost, and when homeowners compare local HVAC options.

Quick Summary

Likely answer: Restricted airflow, dirty coils, low refrigerant, capacitor failure, duct leakage, or thermostat issues.

Typical cost range: Many basic AC repairs fall around $150 to $650; compressor or refrigerant-leak repairs can run higher.

Next comparison: Compare repair cause, urgency, system age, and local HVAC service options.

Cost and Decision Table

ScenarioEstimated RangeUrgencyWhat It Means
Clogged filter or airflow restriction$20-$180Low to mediumCheck first if airflow is weak.
Capacitor, contactor, thermostat, drain issue$150-$650MediumCommon service-call repairs.
Refrigerant leak or compressor problem$700+HighUsually requires licensed HVAC service.

Why the AC Runs but Does Not Cool

A central AC needs airflow, heat exchange, refrigerant pressure, and electrical startup parts to work together. If one part fails, the fan may still run while the house stays warm.

What to Check Before Comparing Repair Options

Check the thermostat mode, filter, breaker, outdoor-unit airflow, and whether the issue affects one room or the whole house. Stop at refrigerant, compressor, and electrical work.

When the Issue Is More Than a Simple Reset

Frozen lines, buzzing, burning smells, short cycling, or repeated warm-air cycles point to a deeper service issue.

Mistakes to Avoid

Running the AC for hours while the refrigerant line is frozen.

Comparing only the lowest service-call fee instead of full repair scope.

Ignoring weak airflow from multiple vents.

Assuming a thermostat reset solves recurring warm air.

Waiting through peak heat when the system is short cycling.

FAQ

Why is my AC running but not cooling?

Common causes include restricted airflow, dirty coils, low refrigerant, failed electrical parts, duct leakage, or thermostat issues.

How much does AC repair cost?

Basic repairs often fall around $150 to $650, while compressor or refrigerant-leak repairs may cost more.

Can a dirty filter stop cooling?

Yes. A clogged filter can reduce airflow enough to hurt cooling and contribute to coil freezing.

Should I turn the unit off?

If the unit is frozen, short cycling, buzzing, or producing electrical smells, turning it off and comparing service options is safer.

What should an HVAC quote include?

It should explain the diagnosis, parts, labor, warranty, and whether follow-up service is included.

By James Carter