Hayward pressure switch FDXLWPS1930 replacement for Universal H-Series Low NOx — Black, post‑5/11/2010

This replacement pressure switch restores correct water-flow sensing in compatible Hayward Universal H-Series Low NOx gas pool heaters. It is a factory-style part manufactured to fit specific H-Series models and to reconnect the heater's safety and control systems that rely on accurate water pressure detection.

Which Hayward heater models work with this pressure switch?

The FDXLWPS1930 is designed for a defined set of Universal H-Series Low NOx models. Confirm your heater model and serial date before ordering to ensure compatibility.

• Compatible models: H150FDN, H150FDP, H200FDN, H200FDP
• Also fits: H250FDN, H250FDP, H300FDN, H300FDP
• Included: H350FDN, H350FDP, H400FDN, H400FDP
• Only for units manufactured after 5/11/2010 (serial # starting at 21130005101018001 or later)

How does this pressure switch affect heater operation?

The switch monitors water pressure and tells the heater when it is safe to ignite. If the switch is faulty, the heater may not fire or could shut down unexpectedly; replacing it re-establishes reliable flow sensing without changing your heater's control logic.

• Detects low or absent water flow to prevent burner operation
• Sends a clear electrical signal to the heater control board
• Factory-fit dimensions and connections for listed H-Series models
• Maintains original safety and performance parameters

What should I check before installing this replacement part?

Verify the heater model number and manufacturing date, and confirm the symptom is a pressure-switch fault rather than wiring or plumbing issues. If unsure, consult a licensed technician to avoid incorrect replacement or injury.

• Inspect heater serial number—must be after 5/11/2010
• Confirm visible signs of switch failure (no ignition, error codes)
• Check wiring harness and plumbing for leaks or damage
• Have proper tools and follow manufacturer installation guidance

How do I install the Hayward FDXLWPS1930 safely?

Installation requires turning off power and fuel, draining pressure when appropriate, and removing the old switch before mounting the new unit. Follow the heater manual or hire a qualified service technician to ensure electrical and gas safety standards are met.

• Shut off electrical supply and gas before beginning
• Depressurize and dry the plumbing connections
• Transfer wiring and secure the replacement with original fittings
• Test operation and check for leaks after reassembly

Who this is for: This replacement part is intended for pool owners, service professionals, and maintenance technicians who operate or repair Hayward Universal H-Series Low NOx pool heaters built after May 11, 2010. Choose this switch when your heater's flow-sensing device has failed or shows related error codes, and you need a like-for-like OEM-style component to restore proper, safe heater function.