Hard Lockout 6: Stack High Limit

Condition

  • Sage Flue Gas sensor detected temperatures in excess of 214°F.

Possible Cause

  • Heat exchanger needs to be cleaned.
    • Refer to I&O Service and Maintenance Guide
  • Boiler over-fired.
    • Loads may be too small for the boiler size
  • Air-fuel mixture out of adjustment – consult factory.