Glow-worm
Glow-worm Temperature Sensor S1027300
Glow-worm temperature sensor for the storage vessel on Xtrafast, Xtramax, Isofast, Isomax and Themaclassic Plus appliances.
£25.45
£21.21 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Glow-worm S1027300 is a temperature sensor (thermistor) for the storage vessel on a range of Glow-worm and Saunier Duval gas boilers. It monitors stored water temperature and feeds that reading back to the appliance's control board so the boiler can regulate domestic hot water. It is listed as a replacement for the earlier code 05725000.
Signs this part needs replacing
- Domestic hot water runs hot then cold, or the temperature drifts from the set point
- The appliance reports a sensor or thermistor fault code
- Stored water temperature reads implausibly high or low on the display
- The boiler locks out or cycles during a hot water draw-off
- Visible damage, corrosion or heavy scale on the sensor probe or its lead
Before you order
- Confirm your appliance model against the fitment list above
- On Isofast Condens F35E and Isomax F28 E2, check the serial number against the cut-off shown
- Check the part number on the sensor currently fitted to the storage vessel
- Confirm the sensor is for the storage vessel rather than the heating circuit
Compliance
| GC number | E37-302 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| GLOWWORM GLOWWORM XTRAFAST 120 | — | — | — | |
| GLOWWORM GLOWWORM XTRAFAST 2000 | — | — | — | |
| GLOWWORM GLOWWORM XTRAFAST 96 | — | — | — | |
| GLOWWORM GLOWWORM XTRAMAX | — | — | — | |
| GLOWWORM XTRAFAST 120 | 47-047-26 | 47-047-26 | — | — |
| GLOWWORM XTRAFAST 2000 | 47-047-10A | 47-047-10A | — | — |
| GLOWWORM XTRAFAST 96 | 47-047-25 | 47-047-25 | — | — |
| GLOWWORM XTRAMAX | 47-047-15 | 47-047-15 | — | — |
| GLOWWORM XTRAMAX HE | 47-047-29 | 47-047-29 | — | — |
| SAUNIER DUVAL SAUNIER DUVAL ISOFAST CONDENS F35E AFTER SERIAL No 0400446159 | — | — | — |
Showing 10 of 20 compatible appliances.
Documents & drawings
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