Honeywell Control box DMG972-N mod. 04 0452004

The Honeywell DMG972-N mod. 04 control box (SKU 0452004) is a two-stage control unit for gas or oil burners, suitable for forced draught and combi burners. It operates at a supply voltage of 220–240 V and includes an air proving switch with one working contact rated at 4 A, 230 V. The device features stray light monitoring with a 5-second response time and has a net weight of 0.19 kg. Its protection class is IP40, and it can be mounted in any position.

When selecting a replacement control box of this type, verify the operating voltage (220–240 V) and the air proving switch rating (4 A, 230 V) match the burner's requirements. Ensure the mounting position is compatible, as this type allows any orientation. Check the physical dimensions and wiring base compatibility, as the weight including wiring base is 190 kg (likely a typo for 190 g). Confirm the fuel type (gas or oil) and burner stage (two-stage) are supported.

Common failures of this control box type include malfunction due to stray light interference, which may cause the burner to shut down or fail to start. If the air proving switch fails, the burner may not receive the correct air pressure signal, leading to ignition failure or unsafe operation. Check the wiring connections and the condition of the flame detection circuit, as issues here can cause intermittent operation or lockout.