Astralpool Hurlcon Gas Heater & Halo Temperature Sensor - Thermistor - HX JX MX Viron ICI HiNRG Halo

Astralpool Hurlcon Gas Heater & Halo Temperature Sensor - Thermistor - HX JX MX Viron ICI HiNRG Halo

Genuine Astralpool / Hurlcon temperature sensor lead, also known as a thermistor lead, for most Astralpool and Hurlcon gas pool and spa heaters with a digital thermostat. Also used in Astralpool Halo temperature sensor kits.

• Physically Stocked, unlike most "drop-shipping" websites.
• Shipped from VIC, NSW, WA, QLD

This replacement sensor is commonly used to correct incorrect water temperature readings, sensor-related thermostat faults, and F0 / FO temperature sensor errors on many post-2001 Hurlcon and Astralpool heaters.

Part Details

• Part type: Temperature sensor lead / thermistor lead
• Manufacturer: Astralpool / Hurlcon
• Part number: 70276
• Length: ~1.5m
• Commonly called: Temp sensor, temperature sensor, thermistor, sensor lead
• Replaces: Older black, red and yellow wired temperature sensor leads on compatible digital thermostat heaters

Compatible Astralpool & Hurlcon Heaters

This sensor suits many post-2001 digital thermostat Astralpool and Hurlcon gas heaters & Halo controllers, including the following model families:

• HX Series: HX 70, HX 120, HX 150
• WX / Wilton Series: WX 70, WX 75, WX 120
• MX Series: MX 125, MX 150, MX 200, MX 250, MX 300, MX 350, MX 400, MX 500
• JX Wall-Mount Series: JX 130, JX 160
• Viron & Viron eVo Series: Viron 250, Viron 350, Viron 450
• HiNRG Series: HiNRG 175, HiNRG 250, HiNRG 400
• ICI Series: ICI 200, ICI 400
• Hurlcon Boilers: HB 200, HB 250, HB 300, HB 400, HB 500
• Jacuzzi gas heaters: J-HN250C, J-HN400C
• Halo Chlorinator Control Systems

Viron Heat Exchanger Sensor Note

On some Viron heaters, this sensor is also used as the heat exchanger temperature sensor. Check your existing sensor location and wiring before ordering.

F0 / FO Error & Fault Diagnosis

• A failed or wet temperature sensor can cause an F0 / FO fault.
• It may also cause incorrect or unstable displayed water temperature readings.
• The heater’s displayed temperature is based on water passing through the heater, so the pump must be operating correctly for the temperature reading to be meaningful.
• If the fault returns after replacing the sensor, check the brass well, wiring, thermostat PCB and overall heater condition.

Important Brass Well Information

Temperature sensors often fail because water has leaked into the brass sensor well. If the old sensor is swollen, corroded, difficult to remove, or the well has water inside it, the brass well should also be replaced.

Some newer replacement sensors can be slightly larger than earlier sensor leads. If the sensor does not fit correctly into the old well, replace the brass well rather than forcing the sensor.

• Brass well for Hurlcon / Astralpool temperature sensor

Related Heater Parts

• HX / WX gas heater seal and bypass kits
• HX, JX, MX, Viron and HiNRG gas heater service kits

Confirm product is correct before ordering. Contact us if unsure.

Manufacturer Catalogues, Diagrams & Part Numbers

Need exploded views, spare part numbers, product numbers, diagrams or more product information? See the manufacturer catalogues: Astralpool Catalogue 2026 | Zodiac Catalogue 2026

Interactive Parts Diagrams

Find this part on our interactive heater parts diagrams — each one opens the full exploded view and parts list:

• Astralpool / Hurlcon HX 120 Gas Heater — Diagram & Parts