Hayward Pressure Switch for FD Series Heaters | FDXLWPS1931

Description

The Hayward Pressure Switch (FDXLWPS1931) is the OEM replacement water pressure switch for Hayward FD Series pool and spa heaters.

IMPORTANT: PROFESSIONAL SERVICE REQUIRED
Gas and electrical heater components must be serviced by a licensed pool professional or qualified HVAC technician. Do not attempt to service gas or high-voltage components without proper certification.

This pressure switch monitors water flow conditions within the heater and prevents the unit from firing when water pressure is insufficient. By blocking ignition under low-flow conditions, it protects the heat exchanger and other internal components from heat damage caused by inadequate water circulation.

Specifications

Poolaroo Pro Tip

Before replacing the pressure switch, confirm the heater’s water flow rate is within the manufacturer’s specified range. A faulty pressure switch can mimic symptoms of inadequate flow — such as the heater failing to ignite — but replacing the switch without addressing an underlying flow restriction will not resolve the issue. Always have a licensed pool professional or qualified HVAC technician perform diagnosis and replacement of heater components.