Common HVAC Troubleshooting Steps

When your HVAC system isn't working as expected, some basic troubleshooting can often identify simple issues or help you provide more information to a technician. Safety first: If you are uncomfortable with any step, or if it involves electrical components beyond simple checks, always call a qualified HVAC professional.

System Not Turning On:

• Check Thermostat Settings: Ensure it's set to "Cool" or "Heat" mode and the setpoint is appropriate. Check batteries if it's battery-powered.
• Check Circuit Breakers: Look for tripped breakers in your electrical panel for both the indoor unit (furnace/air handler) and outdoor unit (condenser).
• Check Power Switches: Ensure power switches near the indoor and outdoor units are turned on.
• Check Condensate Drain Pan/Switch: A clogged drain or full pan can trigger a float switch that shuts down the system.

Insufficient Cooling or Heating:

• Check Air Filter: A dirty or clogged air filter is a very common cause. Replace if necessary.
• Check Vents and Registers: Ensure they are open and not blocked by furniture or drapes.
• Outdoor Unit (Cooling): Check if the condenser coil is dirty or blocked by debris/vegetation. Clean carefully if accessible.
• Check Ductwork: Look for obviously disconnected, crushed, or leaky ducts in accessible areas like basements or attics.

System Runs Constantly:

• Thermostat Setting: Is the setpoint too extreme for current conditions?
• Air Filter: A very dirty filter can cause this.
• Refrigerant Level (Cooling): Low refrigerant can cause the system to run longer without reaching the setpoint (professional check needed).
• Undersized System or Major Air Leaks: The system might be too small for the load, or there might be significant air leakage from the building.

Strange Noises:

• Rattling: Could be loose panels, screws, or debris in the blower or outdoor unit.
• Squealing/Grinding: Often indicates motor bearing issues. Turn off the system and call a pro.
• Banging/Clanking: Could be a loose part or a more serious issue. Professional inspection needed.

Disclaimer: This guide is for general informational purposes only. HVAC systems are complex and can be dangerous to work on if you're not qualified. Always prioritize safety and consult a licensed HVAC professional for any repairs or maintenance beyond simple checks like filter changes or thermostat settings.