Kromschroder Gas pressure switch DG50UG-9 84447024

The Kromschroder DG50UG-9 is a mechanical diaphragm pressure switch designed for monitoring pressure changes in gas or air. It operates with a NBR diaphragm and a housing made of glass fibre reinforced PBT plastic with a lower housing section of AlSi 12. The switch is silicone-free and has low gas release, suitable for use with natural gas, town gas, LPG (gaseous), flue gas, biogas (max. 0.1 %-by-vol. H2S), and air. It features a connection thread of M16 x 1.5, screw terminals for electrical connection, and is rated for safety class 1. The medium and ambient temperature range is -20 to +80 °C, with a storage temperature of -20 to +40 °C.

When selecting a replacement pressure switch of this type, ensure the connection thread (e.g., M16 x 1.5) matches the existing port, and the electrical connection (screw terminals) is compatible with the wiring. The switch must be suitable for the medium (gas or air) and the pressure range of the application. Check the enclosure rating (IP54 or IP65) and the line diameter (0.5 to 1.8 mm) for the cable. Mounting orientation and the direction of pressure change (increase or decrease) should be considered, as the switch can be set to trip on either.

Common failures of diaphragm pressure switches include diaphragm rupture or leakage, leading to loss of pressure sensing and failure to switch. Symptoms may include the burner not starting, unexpected shutdowns, or the switch failing to respond to pressure changes. Check for cracks or wear in the diaphragm, and verify the electrical continuity of the switch contacts. Also, inspect the housing for damage or contamination that could affect operation.