Lennox HVAC Error Code E22: How to Fix It

Q: What does Lennox error code E22 mean?

Error code E22 indicates an airflow proving switch fault. The system detected that the airflow switch did not close or open properly, which can be due to a dirty filter, blocked vent, faulty switch, or wiring issue.

Q: How do I reset Lennox error code E22?

Turn off the power to the system at the breaker for 5 minutes, then turn it back on. Alternatively, turn the thermostat off and on. If the error returns, further troubleshooting is needed.

Q: Is it safe to continue using my HVAC system with error code E22?

No, it is not recommended. The airflow proving switch is a safety device. Operating the system with this fault could cause incomplete combustion or overheating, leading to damage or safety hazards. Address the issue before using the system.

Q: How much does it cost to fix Lennox error code E22?

If you DIY, the cost is minimal (e.g., a new air filter or switch). If you call a professional, expect $100-$200 for diagnostic fees plus parts and labor. A new airflow switch costs around $20-$50.

Q: Can a dirty air filter cause error code E22?

Yes, a dirty air filter is a common cause. It restricts airflow, preventing the switch from detecting proper pressure. Always check and replace the filter first.

Abstract

Error code E22 on your Lennox HVAC system indicates an airflow proving switch fault. This means the system detected a problem with the airflow switch, which could be caused by a blocked vent, a faulty switch, or a wiring issue. Follow the steps below to diagnose and fix the problem safely.