High
THERMISTOR on Baxi Solo 2

Your boiler has detected that its temperature sensor is not working correctly, which means it cannot tell how hot the water is and has stopped running for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Lights: On Flash On. Thermistor resistance out of range (0.5kΩ - 20kΩ) or wiring/PCB fault.

From this model's manual
Verified against the Baxi/Baxi Solo 2 installation & service manual, page 52.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 22 fault codes on the Solo 2

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

FAN LOCKOUTIgnition LockoutLights: Flash On FlashLights: Flash On OnLights: Flash, Flash, OnLights: Flash, Off, FlashLights: Flash, Off, OnLights: Flash, On, FlashLights: Flash, On, OnLights: Off Off OffLights: Off, Off, OffLights: On Flash FlashLights: On Flash OnLights: On Off OnLights: On On FlashLights: On On OnLights: On, Flash, FlashLights: On, Flash, OnLights: On, Off, FlashLights: On, On, FlashOVERHEAT LOCKOUT

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