Kromschroder Gas pressure switch DG150U-3N 84447513

The Kromschroder DG150U-3N (SKU 84447513) is a gas pressure switch with an adjustable pressure range of 30–150 mbar. It monitors gas pressure in burner and boiler systems, closing or opening electrical contacts when the setpoint is reached. This device is designed for use with gas media and provides a safety signal to the burner control, preventing operation outside safe pressure limits. It features manual adjustment via a wheel and has an IP54 protection rating.

When selecting a replacement pressure switch of this type, verify the medium (gas only), the required pressure range and differential, the connection type (thread or hose spigot), and the electrical contact rating. The setpoint must be adjustable to match the application's pressure stage. Installation involves connecting the impulse line to the pressure tap and wiring the switch to the burner control, ensuring the setpoint is calibrated correctly.

Common failure modes include a torn diaphragm, blocked impulse tube, or drifted setpoint. These issues typically cause burner lockouts that resemble ignition faults. To diagnose, check the pressure switch and its impulse line for damage or blockage, and verify the setpoint against the actual system pressure.