Kromschroder Gas vacuum sensor DG18I-3 84447050

The Kromschroder DG18I-3 gas vacuum sensor (SKU 84447050) is a pressure switch designed to monitor increasing and decreasing gas or air pressure. It has an adjusting range of -2 to -18 mbar and is suitable for natural gas, town gas, LPG (gaseous), flue gas, biogas (max. 0.1% by vol. H2S), and air. The device features a glass fibre reinforced PBT plastic housing with a lower housing of AlSi 12, an NBR diaphragm, and an IP54 protection class. It weighs 321 g, has a line diameter of 0.5–1.8 mm, and a line entrance thread of M16 x 1.5. The product meets safety class 1 and complies with EN 13611:2015+AC:2016 and EN 1854:2010 standards, with production surveillance and tested type sample certification.

When selecting a replacement pressure switch of this type, ensure the adjusting range, gas type compatibility, and electrical connection (screw terminals) match the application. Verify the line diameter and entrance thread size (e.g., M16 x 1.5) to fit the existing conduit. The protection class (e.g., IP54) must be suitable for the installation environment. Always compare the switch's setpoint range and switching function (increasing or decreasing pressure) with the original part before ordering.

Common failure modes for this kind of pressure switch include diaphragm rupture or leakage, leading to loss of pressure sensing and incorrect burner operation. Symptoms may include the burner failing to start, unexpected shutdowns, or erratic pressure readings. Check for gas leaks around the switch, inspect the diaphragm for damage, and verify the electrical continuity of the switch contacts. Regular maintenance, such as annual tightness and function checks, is recommended to prevent failures.