Honeywell Automatic burner control unit EC7850A1122/U

Honeywell EC7850A1122/U is an automatic burner control unit for sequencing burner operations, flame monitoring, system diagnostics, and fault detection. It operates on 220–240 V, 50–60 Hz, consumes up to 10 W, and has a connected load limit of 2000 VA. The unit is rated for ambient temperatures from -40 to 60 °C and transport temperatures from -40 to 66 °C, with non-condensing humidity up to 85%. It features five LEDs for status indication, a five-function switch, external voltage control, and a communication interface. Process history and lockout status are stored in non-volatile memory. The controller weighs 700 g and measures 127 mm × 127 mm × 133 mm (155 mm with Q7800A base).

Controllers of this type are selected by the mounting base (Q7800A or Q7800B) and the existing wiring configuration. The overall depth varies with the base, so confirm the base type before ordering. Ensure the controller is compatible with the installed Honeywell flame detector. Check that the external voltage control and communication interface connections match the system.