Ma-Ter Pressure switch DR2BD1AB004070

Ma-Ter pressure switch DR2BD1AB004070 monitors the pressure of air, gases, or liquids and switches an electrical circuit when the set point is reached. Its sensing element is a membrane, and the body is made of metal and polymer. The connection thread is 1/4" gas, and it operates in ambient temperatures from -20 °C to +85 °C. The switch is vibration resistant, protected against overpressure, and manufactured in Italy.

When replacing a pressure switch of this type, confirm the medium (air or gas), the required switching range and differential, the connection type (thread or hose spigot), and the electrical contact rating. Verify that the new part has the same switching function (normally open or normally closed) and that its setpoint can be adjusted to match the original specification. Typically, these parts are connected via an impulse tube to the air duct or gas train, and the electrical terminals are wired into the burner control circuit.

Pressure switches of this type commonly fail through a torn diaphragm, a blocked or leaking impulse tube, or a drifted setpoint. When such a failure occurs, the switch contacts may not change state correctly, causing the burner control to prevent start-up or go into lockout. This can be misdiagnosed as an ignition fault. Check the impulse tube for blockage or leakage, inspect the diaphragm for damage, and verify the setpoint against the required value.