Honeywell Gas boiler control unit S4565C1090U

This gas burner control box operates at 220–240 V and uses a flame sensor rod. It is EN 298 compliant, resets via a button or power interruption, supports an external LPG valve, and provides extended ignition time. On flame loss, it repeats the starting sequence with a pre-purge. It includes an auxiliary fan (suffix c) and an airflow control relay that starts the fan when airflow is absent. It is designed for Honeywell VK41 gas regulators.

Control units of this kind are mounted directly on the gas regulator via a top connector and can be installed at any angle within 90° of the vertical. They are selected by supply voltage and ignition system (spark or pilot); the suffix 'c' denotes an auxiliary fan. Before ordering, confirm compatibility with the gas regulator series.

If the flame does not establish within the safe ignition time, the control unit locks out. A flame loss during operation triggers a restart with pre-purge. If the airflow control relay does not detect airflow during pre-purge, the unit stays in standby with the fan running.