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.
FDXLTER1931 | Hayward Thermistor For HC-Series HDF400
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CA P65 Warning: Cancer and reproductive harm. www.p65warnings.ca.gov
OEM Hayward Thermistor FDXLTER1931 is a critical sensing component for Universal HC-Series HDF400 heaters, precisely regulating water temperature to maintain consistent heating performance. Engineered for compatibility with standard Cupro Nickel heat exchangers, it provides excellent resistance to saltwater and chemical exposure, making it ideal for demanding pool environments. Its accurate readings and robust construction ensure safe heater operation and prevent overheating or temperature fluctuations. This thermistor plays a vital role in preserving system efficiency and extending the service life of your pool heater.
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Precise Temperature Control for HDF400: Maintains accurate water temperature readings for optimal operation and safety in Hayward HC-Series heaters
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Designed for Salt and Chemical Resistance: Compatible with Cupro Nickel heat exchangers, ensuring strong resistance to corrosion from harsh water conditions
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Ensures Long-Term Reliability: Durable OEM build handles frequent exposure to heat and chemicals without performance degradation over time
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Maintains Heating Efficiency: Allows the heater to operate within its target range, reducing strain on internal components and improving energy efficiency
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Protects Overall Heater Lifespan: Plays a key role in preserving system longevity by preventing overheating and supporting proper temperature cycling
- Hayward Universal HC-Series HDF400 Heaters
