Medium
8+ on Biasi Antares 25C M300V.2025 SM

Your boiler's outside temperature sensor has failed, meaning the system doesn't know how hard it needs to work to heat your home based on the weather.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

External NTC probe failure.

From this model's manual
Verified against the Biasi/Biasi Antares Combi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 80 fault codes on the Antares 25C M300V.2025 SM

Seeing a different code? Every code this model can display, in one place.

1+2+3+4+5+6+7+10 +11 +12 +13 +14 +15 +16 +18 +19 +20 +21 +22 +23 +24 +25 +26 +40 +42 +44 +50 +62 +65 +68 +77 +78 +79 +89 +91 +9696 +9799E01E02E03E04E05E06E07E08E10E11E12E13E14E15E16E18E19E20E21E22E23E24E25E26E40E42E44E50E62E65E68E77E78E79E89E91E96E97E99L1

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