Kromschroder Air pressure switch DL3K-3W 84444600

The Kromschroder DL3K-3W is a mechanical diaphragm pressure switch designed to monitor positive, negative, or differential pressure of air or flue gas. It has an adjusting range of 0.2 to 3 mbar and features a tempered LSR diaphragm system. The housing is made of glass fibre reinforced PBT plastic with low gas release, and electrical connection is via screw terminals. The switch operates with a microswitch to EN 61058-1, complies with safety class II, and is certified to CE-0085AP0466. It meets standards EN 13611:2015+AC:2016 and EN 1854:2010, with a designed lifetime of 10 years and a net weight of 0.2 kg.

When selecting a replacement pressure switch of this type, verify the required pressure range, medium compatibility (air or flue gas), and electrical connection method. Ensure the switch's setpoint range covers the application's needs and that the mounting configuration (e.g., tube connection) matches the existing setup. Check the electrical ratings and safety certifications to comply with local regulations. For installation, follow the manufacturer's instructions for torque settings (e.g., cover screw and strain relief at 65 Ncm) and ensure proper sealing to avoid leaks.

Common failure modes for diaphragm pressure switches include diaphragm rupture or fatigue, leading to loss of pressure sensing or false triggering. This may cause the burner to fail to start, shut down unexpectedly, or operate without proper air or flue gas pressure monitoring. Electrical contact issues in the microswitch can result in intermittent signals or complete loss of function. Check for visible damage to the housing or diaphragm, verify the setpoint with a manometer, and test continuity of the switch contacts.