Start With The Simple Checks
HVAC troubleshooting guidance without the guesswork.
Use this guide to check the simple things first, understand what the issue might mean, and know when it is time to call a professional.
Before You Start
Useful checks, clear warnings, and help when you need it.
- Check the simple items first, like thermostat settings, filters, breakers, and airflow.
- Read what the symptom may point to before a small issue turns into a bigger repair.
- Call right away for gas smells, burning odors, electrical issues, active leaking, or loud noises.
Safety First
Some checks are safe for homeowners, like replacing filters, confirming thermostat settings, and checking breakers. Anything involving gas, refrigerant, wiring, burners, internal components, or burning smells should be handled by a trained professional.
Choose Your System
Select the equipment you are having trouble with to jump directly to common issues.
AC Problems
Not cooling, freezing up, or leaking.
Furnace Problems
No heat, cycling off, or strange noises.
Heat Pump Problems
Iced over, constant running, or stuck modes.
Mini-Split Problems
Not heating/cooling, remote issues, or leaks.
Thermostat Problems
Blank screen, wrong settings, or no response.
Air Quality Problems
Excessive dust, musty air, or high humidity.
Humidifier Problems
Not adding moisture or leaking water.
Not Sure What's Wrong?
Need help diagnosing an unknown issue?
AC Troubleshooting
Furnace Troubleshooting
Heat Pump Troubleshooting
Mini-Split Troubleshooting
Thermostat & Electrical Problems
Indoor Air Quality Troubleshooting
Humidifier Troubleshooting
When to Call a Professional Immediately
If you experience any of these major warning signs, stop troubleshooting immediately and contact an expert. Your safety is paramount.
Next Best Step
Related HVAC Services
Move from troubleshooting to the service page that matches the issue you found.
Troubleshooting FAQ
Common questions about diagnosing HVAC problems at home.
Still Not Sure What's Wrong?
Our team is here to help. Call A & A Professional Cooling and Heating for professional diagnostics and honest recommendations.