HVAC TROUBLESHOOTING GUIDE

AC Won't Turn On: Common Causes & Next Steps

An air conditioner that does nothing can have a power, thermostat, safety-switch, or equipment problem.

Call to request heating or cooling service in Littleton.

START HERE

Safe checks before scheduling service

Verify the thermostat display is active and cooling is selected.
Check the HVAC breaker once; do not repeatedly reset a breaker that trips again.
Make sure accessible equipment switches have not been turned off accidentally.
Replace a dirty filter if airflow has been neglected.
If the system remains dead, stop there rather than opening electrical panels.

If you encounter exposed wiring, smoke, a gas odor, a carbon-monoxide alarm, or another immediate safety concern, stop troubleshooting and follow the appropriate emergency guidance.

WHEN TO CALL

Move from troubleshooting to diagnosis

If the simple checks above do not resolve the problem, or the same symptom returns, professional diagnosis is usually more useful than continuing to reset or restart the equipment. Describe the symptom and what you have already checked.

WHAT NOT TO DO

Avoid risky shortcuts

Do not bypass switches, defeat safeties, open sealed refrigerant systems, adjust gas valves, or repeatedly reset a breaker that trips. Those steps can create additional risk or obscure the original problem.

LOCAL HVAC HELP

Still having trouble? Call for local HVAC help

Tell us what your heating or cooling system is doing and request service in Littleton.

Call 303-632-9562

RELATED HVAC HELP

AC Won't Turn On: Common Causes & Next Steps

Safe checks before scheduling service

Move from troubleshooting to diagnosis

Avoid risky shortcuts

Still having trouble? Call for local HVAC help

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