Why is my AC not working?

The most common causes of AC failure are a tripped circuit breaker, dirty air filter blocking airflow, a failed capacitor, low refrigerant, a frozen evaporator coil, or a failed compressor. Check the breaker and filter first — those are free fixes. If the system is running but not cooling, a refrigerant or capacitor issue is likely.

What should I do if my AC stops working in summer?

First: check the thermostat is set to cool, check the circuit breaker, and replace the air filter if it's clogged. If the system runs but won't cool, turn it off and call a contractor — running a system with a refrigerant leak or frozen coil causes more damage. Request emergency service and describe the symptom.

How much does emergency AC repair cost?

Emergency after-hours AC service typically adds $50–$150 to the standard repair cost. The repair itself ranges from $150–$600 for most common issues. Compressor replacement is more expensive — $800–$2,500. If the compressor has failed on an older system, replacement is usually more economical than repair.

AC Not Working? What to Do Right Now

Check These First (Before Calling Anyone)

Check the thermostat. Make sure it's set to COOL and the temperature is set below the current room temperature. Check the batteries.
Check the circuit breaker. Go to your electrical panel and look for a tripped breaker labeled AC, HVAC, or Air Handler. Reset it if tripped.
Check the air filter. A completely clogged filter blocks airflow and causes the system to freeze or shut down. Replace it if it's gray and clogged.
Check the outdoor unit. Is it running? If it's running but blowing warm air, you likely have a refrigerant issue. If it won't turn on, could be a capacitor.
Check the drain pan. Many systems have a safety float switch that shuts the system off if the condensate drain is clogged. Check for standing water near the air handler.

If It Still Won't Work — Common Causes and Fixes

Running but not cooling: Low refrigerant leak or failed capacitor. Do not run the system — turn it off and call a contractor. Running with a refrigerant leak causes compressor damage.
Frozen evaporator coil: Ice visible on the indoor unit. Turn the system to FAN ONLY for 2 hours to defrost, then back to COOL. If it freezes again, refrigerant or airflow issue — call a contractor.
Outdoor unit not running: Likely a failed capacitor — a common, inexpensive repair ($150–$350). Do not attempt to replace it yourself; capacitors hold lethal charge.
Short cycling (turns on and off repeatedly): Could be refrigerant, oversized system, or thermostat issue. Needs professional diagnosis.
Compressor failure: If you hear a grinding noise or the outdoor unit hums but won't start, the compressor may have failed. This is expensive — get a replacement quote alongside the repair quote.

Full guide: AC Repair Cost Guide

When It's a Genuine Emergency

For most people in air-conditioned climates, an AC failure is uncomfortable. For the elderly, infants, and people with certain medical conditions, it can be dangerous. If indoor temperatures exceed 90 degrees and you have vulnerable household members, treat it as an emergency and request same-day service.

Use the form below and note the urgency. Most local contractors prioritize emergency calls.

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AC Not Working — What to Do Right Now

Check These First (Before Calling Anyone)

If It Still Won't Work — Common Causes and Fixes

When It's a Genuine Emergency

Find Emergency AC Repair in Your City

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