Emergency
Flue temperature probe NTC lock out on Biasi Garda Plus HE M110.24SM/E

Your boiler has safely shut down because a sensor has detected that the exhaust gases leaving through the flue are too hot.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Flue temperature probe NTC lock out

From this model's manual
Verified against the Biasi/Biasi G101 Biasi Garda Plus He M110 24sm E Service Manual 4797031 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 is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

Err 04View →Err 02View →

All 7 fault codes on the Garda Plus HE M110.24SM/E

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

Excessive temperature on primary circuitFaulty c.h. temperature probe NTCFaulty d.h.w temperature probe NTCFaulty Electronic control/ignition p.c.b.Faulty flue temperature probe NTCFlame detection error

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