Huba Pressure switch HC015

The Huba Pressure switch HC015 is a differential air pressure switch designed for gas boilers. It controls the fan operation and flue gas exhaust process, with a pressure range of 1.05–1.05 mbar and a switching differential of 0.15 mbar. This switch ensures that air pressure in the system is within the permitted band, allowing the burner control to proceed with ignition or running sequences. It is suitable for various gas boiler models, providing flexibility in component selection and replacement.

Parts of this type are selected by the medium (air or gas), the switching range and differential, the connection type (thread or hose spigot), contact rating, and applicable approval class. The switching range and differential must match the system's operating pressure and required safety margins. Connection size and type must fit the impulse line or tapping on the appliance. Contact rating must be adequate for the burner control input circuit. When replacing, verify the switching range, differential, and connection on the existing part, and check that the impulse line is clean and sealed.

Typical failures that lead to lockouts include a torn diaphragm, a blocked impulse tube, or a drifted setpoint. When such a failure occurs, the pressure switch opens its contact, and the burner control goes to lockout, preventing unsafe operation. To diagnose, check the diaphragm for damage, ensure the impulse line is clear and sealed, and verify the setpoint is correctly adjusted.