York S1-024-35261-000 Pressure Switch 1"WC SPNO Close On Fall

The York S1-024-35261-000 is a pressure switch that works to detect or control the HVAC depending on changes in pressure. It is designed for use at a low pressure of about 1" water column. The switch is of single pole normal open type, which implies that the electrical contacts are open at normal pressure. The pressure switch is integrated with a sensing element for pressure variation. When the system pressure is below the set point of 1" WC the detecting element closes the connections of the switch. The close-on-fall action enables the switch to control different parts of the HVAC or trigger an alarm based on the pressure.