Cause of error code A24

3 flame failures. 

Solution for error code A24

1. Inspect harness connection Flame Sensor. Is connection clean and secure?
Yes: -> 2.
No: Replace Flame Sensor or harness.

2. Remove Flame Sensor. Is rod free of contamination? 
Yes: -> 3
No: Clean or replace Flame Sensor. 

3. Follow OPERATING INSTRUCTIONS to initiate boiler operation. Enter Installer Menu, Boiler Status, Flame Signal. Is flame signal greater than 3.7 uA?
Yes: Replace Control Module. 
No: Replace Flame Sensor and Burner.