Error Code E 291
High Lennox EL296UHV Error Code E 291: Heat Air Flow Restricted Below Minimum
TL;DR
Your furnace has detected that airflow is restricted below the minimum safe level. Check and replace your air filter immediately, and make sure all vents are open. If the filter is clean and vents are open, the blower motor may need professional attention. Most likely cause: dirty air filter. Disclaimer
This article is for informational purposes only and does not guarantee the accuracy or completeness of the information provided. Always turn off power and gas supply before attempting any repairs. If you smell gas, leave immediately and call your gas company. Consult a licensed HVAC technician for diagnosis and repair. Any actions taken based on this information are at your own risk. What Does Code E 291 Mean?
Your furnace has detected that airflow is restricted below the minimum safe level. Check and replace your air filter immediately, and make sure all vents are open. If the filter is clean and vents are open, the blower motor may need professional attention.
Common Causes
| Cause | Likelihood | DIY? |
|---|---|---|
| Dirty air filter | Most common | ✓ DIY fix → |
When to Call a Professional
Contact a licensed HVAC technician if:
- Basic troubleshooting did not resolve the error
- You smell gas at any point during the process
- You are not comfortable working around gas lines or electrical components
- The unit needs a gas valve, control board, or motor replacement
✓ Verified against manufacturer service manual — March 2026