Honeywell 23 troubleshooting answers
1 question with answers cited from the manufacturer manuals.
- 0Honeywell RM7800 Fault 23: Airflow not proven in prepurge, what to check?
Fault 23 on a Honeywell RM7800 series relay module indicates that the combustion airflow interlock did not close during the prepurge cycle. This prevents the furnace from purging and locks out the system before any fuel …