Lochinvar Pressure Switch WC

Lochinvar OEM pressure switches (water column, or WC, rated) are replacement safety and control components for Lochinvar boilers and water heaters. Each switch senses air or gas pressure and opens or closes its electrical contacts at a calibrated set point. These parts are also sold as air pressure switches, low air pressure switches, blocked flue switches and draft switches.

Key Features:

• Calibrated WC set point: each switch is factory-set to a specific inches-of-water-column value so the system responds at the pressure it was designed for.
• Combustion safety: the switch confirms the inducer or vent blower is moving enough air before ignition. It helps prevent operation when the flue is blocked or the venting is restricted.
• Electrical switching: depending on the part, the switch uses an SPDT (single pole, double throw) or SPST (single pole, single throw) contact configuration.
• Diaphragm-style sensing: a pressure-sensitive diaphragm gives reliable, repeatable response through repeated heating cycles.
• Genuine OEM replacement: built to Lochinvar specifications so it restores the unit's original operating behavior after a pressure switch lockout or ignition failure.

Lochinvar has produced water heating and boiler equipment since 1939 and serves both residential and commercial applications. Pressure switch set points differ between models and are safety-critical, so match the WC rating to the one specified for your unit. Select the exact variant below by its part number.