Kromschroder Gas pressure switch DG50N-3 84447720

The Kromschroder DG50N-3 gas pressure switch (SKU 84447720) is a diaphragm-type pressure switch designed to monitor gas or air pressure, switching or locking off when pressure rises or falls outside the set range. It has an adjusting range of 2.5 to 50 mbar and is suitable for use with natural gas, town gas, LPG (gaseous), flue gas, biogas (max. 0.1% by vol. H2S), and air. The switch is silicone-free, with a NBR diaphragm, glass fibre reinforced PBT plastic housing, and a lower housing section made of AlSi 12. It features screw terminals, an M16 x 1.5 line entrance, and is rated IP 54. The device complies with EN 13611:2015+AC:2016 and EN 1854:2010, and carries certification CE-0085AP0467.

When selecting a replacement pressure switch of this type, ensure that the adjusting range, maximum medium and ambient temperatures, and electrical connection (screw terminals) match the application. The line diameter and line entrance thread must be compatible with the existing wiring and conduit. Also verify the enclosure rating (IP 54 or higher) and that the switch is suitable for the specific gas type and pressure conditions. Mounting should follow the manufacturer's instructions, ensuring proper orientation and tightness.

Common failure modes for diaphragm pressure switches include leakage due to diaphragm wear or damage, which can cause the switch to fail to actuate at the set point or to actuate erratically. Symptoms on the equipment may include burner lockouts, failure to start, or unstable pressure control. Regular checks for tightness and functionality are recommended, especially when used with biogas, where inspection intervals should be reduced to six months. If the switch fails to respond to pressure changes, check the diaphragm and the electrical connections.