
Hayward HDF400 Thermistor, FDXLTER1931
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Quick overview
- Genuine Hayward OEM part FDXLTER1931.
- For the HDF400 listed for the Hayward HDF400 heater.
- Temperature sensor a thermistor reports water temperature to the heater control.
- Symptoms of a bad one a drifting or open thermistor shows up as a wrong temperature reading or a sensor fault on the heater.
- Match the part number Hayward uses several different thermistors across its heater lines, so confirm your heater calls for FDXLTER1931.
- UPC 0610377406031 the barcode on the genuine part.
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Frequently bought together

HDF400 Thermistor, FDXLTER1931
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Product details
The Hayward FDXLTER1931 is the thermistor for the HDF400 heater. It is the genuine Hayward part.
What it does
The thermistor is the water temperature sensor. The heater control reads it to decide when to fire and when the pool has reached the set point. When it drifts or fails open, the display shows the wrong temperature or the heater throws a sensor fault and refuses to run.
Before you order
Hayward uses several thermistors across its heater lines. Confirm your heater calls for FDXLTER1931 before ordering.
| Brand | Hayward |
|---|---|
| Manufacturer part number | FDXLTER1931 |
| UPC | 0610377406031 |
| Type | Thermistor |
| Fits | Hayward HDF400 |
| Shipping weight | 0.6 lb |
| Ships | Parcel |
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Questions and answers
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