BoilerFaultCodesBaxi 110 Fault Code
The Baxi 110 fault code means: your boiler has detected that it is overheating and has shut itself down to prevent damage because it cannot circulate water properly.. It appears on 23 Baxi models in our database.
Technical description: Safety Thermostat operated or faulty - Flow & Return Sensors check (Section H/D)
What causes the Baxi 110 fault?
This fault occurs when the water inside your boiler becomes too hot, causing a safety sensor to trip and shut the system down to prevent damage. The most common reason is that the water cannot move around the system properly, often due to an airlock in the pipework or a pump that has failed. It can also happen if your radiator valves are all closed or if there is a physical blockage restricting the flow.
This fault is frequently seen in autumn when heating systems are turned back on after a long summer break, as pump components can seize up from lack of use.
DIY fix possible
Turn off the boiler and allow it to cool down completely.Use a radiator key to bleed all radiators to remove any trapped air.Check the boiler pressure gauge and top it up to 1.5 bar if it has dropped.Turn the boiler back on and press the 'Reset' button.
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A cover plan would handle faults like 110: no call-out fees, no surprise bills.
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Baxi models that show the 110 fault code
Click a model for the full fault code list and model-specific repair notes.
- 100/2 HE Plus Repair: £100-280
- 124 Combi Repair: £180-£350
- 128 Combi Repair: £180-£350
- 615 System 15 Repair: £150-350
- 618 SYSTEM Repair: £150-350
- 624 System 24 Repair: £150-350
- 818 System Repair: £150-300
- 824 SYSTEM Repair: £150-300
- Assure Repair: £150-300
- Duo-tec Combi ErP Repair: £120-220
- Duo-tec Combi GA Repair: £90-180
- Duo-tec Combi HE A Repair: £120-250
- EcoBlue Repair: £150-300
- Ecoblue Advance Combi Repair: £150-250
- EcoBlue System Repair: £180-350
- Neta-tec Combi 24 GA
- Neta-tec Combi 28 GA
- Neta-tec Combi 33 GA
- Platinum Combi HE A Repair: £120-250
- PLATINUM COMPACT 25 COMBI Repair: £150-300
- PLATINUM COMPACT 30 COMBI Repair: £150-300
- PLATINUM COMPACT 36 COMBI Repair: £150-300
- Platinum+ 40 Combi Repair: £120-250
Source
Baxi 110 fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026