Find your parts diagram
Sticker on the pump body (the part with the basket), not on the motor. Motor labels from Century, A.O. Smith or Regal won't match parts.
Label on the side of the tank near the base. Size is in sq ft, e.g. 420 sq ft = C4030 or CCP420.
Rating plate inside the front access panel. Note the BTU and gas type (NG or LP).
Molded into the body or printed on top. Robotic cleaners: on the power supply.
Still not sure? Call (818) 818-6559 and we'll find it for you.
FDXLWPS1931 | Hayward Water Pressure Switch For FD Heaters
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CA P65 Warning: Cancer and reproductive harm. www.p65warnings.ca.gov
OEM Hayward Water Pressure Switch FDXLWPS1931 is a critical safety and performance component for Universal H-Series Low NOx and HDF pool heaters. This switch continuously monitors internal water pressure, ensuring the heater only operates when flow conditions are within a safe range. By preventing the unit from firing under low-flow scenarios, it protects key components from overheating and premature wear. Made from high-quality, corrosion-resistant materials, the FDXLWPS1931 offers reliable functionality for both routine service and emergency repairs, helping to maintain heater efficiency and operational safety over time.
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OEM-Fit for H-Series and HDF Heaters: Precisely designed for seamless compatibility with Hayward Universal Low NOx and HDF400 heater models
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Monitors Internal Water Pressure: Detects insufficient flow and halts ignition to prevent heater damage due to unsafe operating conditions
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Supports Safe Heater Performance: Ensures that heating only occurs under optimal flow, reducing risk of overheating or internal failure
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Built for Harsh Pool Environments: Manufactured with premium materials to withstand prolonged chemical exposure and water pressure fluctuations
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Ideal for Ongoing Maintenance and Repairs: Plays a vital role in sustaining heater longevity and safety through regular servicing or component replacement
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Hayward H-Series Heaters Models: H150FDN, H150FDP, H200FDN, H200FDP, H250FDN, H250FDP, H300FDN, H300FDP, H350FDN, H350FDP, H400FDN, H400FDP, H500FD
- Hayward HDF Series Heater Models: HDF400
