York S1-024-35264-000 1.6″ WC SPNO Close on Fall Pressure Switch

Description

York S1-024-35264-000 Pressure Switch Overview

The York S1-024-35264-000 is a factory OEM pressure switch engineered for use in York heating systems. Rated at 1.6″ WC (inches of water column), this Single Pole, Normally Open (SPNO) switch is designed to close upon a fall in pressure — confirming that the draft inducer motor is generating the correct negative pressure before the control board allows ignition to proceed. This critical safety function helps prevent unsafe furnace operation in the event of a blocked flue, failed inducer motor, or improper venting condition.

Key Features

• OEM York replacement pressure switch — SKU S1-024-35264-000
• Set point: 1.6″ WC (inches of water column)
• Switch configuration: SPNO (Single Pole, Normally Open)
• Action: Closes on pressure fall — activates when inducer creates sufficient negative pressure
• Functions as a safety interlock to verify proper draft/venting before ignition
• Direct OEM replacement for compatible York furnace models

How It Works

During furnace startup, the draft inducer motor runs first to purge combustion gases and establish negative pressure in the heat exchanger. The pressure switch monitors this negative pressure via a hose connected to the inducer housing or collector box. When the pressure drops to the 1.6″ WC set point (pressure falls), the SPNO contacts close, signaling the control board that safe venting conditions exist and allowing the ignition sequence to continue. If the required pressure is not achieved, the switch remains open and the furnace is locked out — protecting against dangerous combustion conditions.

Application

• Designed for use in York brand gas furnaces and air handlers
• Replaces failed or out-of-spec OEM pressure switches
• Recommended for use by qualified HVAC technicians