Kromschroder Gas pressure switch DG 18IG-3 84447051

The Kromschroder DG 18IG-3 (SKU 84447051) is a gas pressure switch designed to monitor low negative pressures in gas and air systems. It has an adjustment range from -2 to -18 mbar and features gold contacts for stable switching. The switch is protected to IP54 and is manufactured in Germany. It is used to ensure safe operation of burners, boilers, and ventilation equipment by responding to pressure drops.

When selecting a replacement gas pressure switch of this type, verify the pressure range, connection size, and electrical rating match the application. The switch must be adjusted to the setpoint specified by the burner manufacturer, and the differential must be appropriate to prevent rapid cycling. Ensure the impulse tube is correctly connected and the switch is mounted in the correct orientation.

Common failures include a torn diaphragm, blocked impulse tube, or drifted setpoint due to vibration or ageing. These can cause repeated burner lockouts, often misdiagnosed as ignition problems. Check the switch's setpoint and impulse line integrity if the burner fails to start or shuts down unexpectedly.