BoilerFaultCodesBaxi 117 Fault Code
The Baxi 117 fault code means: your boiler has too much water in the system, which puts extra stress on the internal parts and may cause it to shut down for safety.. It appears on 10 Baxi models in our database.
Technical description: Water pressure too high
What causes the Baxi 117 fault?
This fault occurs when the water pressure inside your system has risen above the safe operating limit. The most common reason is that the filling loop valve used to top up the boiler has been left slightly open or is leaking water into the system. It can also be caused by a failure in the expansion vessel, which is meant to handle the natural pressure increases that happen when water is heated.
DIY fix possible
Check that the filling loop valves are fully closedSwitch off the boiler and allow the system to coolBleed water from a radiator using a bleed key to reduce pressureMonitor the pressure gauge until it returns to between 1.0 and 1.5 bar
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Baxi models that show the 117 fault code
Click a model for the full fault code list and model-specific repair notes.
- 124 Combi Repair: £0-160
- 200 / 400 Combi Repair: £80-150
- 600 Combi (range) Repair: £90-180
- EcoBlue Repair: £80-160
- Ecoblue Advance Combi Repair: £80-150
- EcoBlue Advance Heat Repair: £80-160
- EcoBlue Heat Repair: £80-160
- EcoBlue Plus Combi Repair: £80-160
- EcoBlue System Repair: £80-120
- Suprima 40 Repair: £80-180
Source
Baxi 117 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 7 July 2026