E117 Medium

Baxi E117 Fault Code

The Baxi E117 fault code means: your boiler has detected that there is too much water pressure in the system, which can cause it to shut down for safety.. It appears on 23 Baxi models in our database.

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.

Technical description: System water pressure high – try bleeding water from your radiators

What causes the Baxi E117 fault?

This fault occurs when the internal water pressure exceeds the safe operating limit, often because the manual filling loop has been left slightly open or the expansion vessel has lost its air charge. When the water in your heating system heats up, it expands; if there is nowhere for this extra volume to go or if the system is overfilled, the pressure rises too high and triggers a safety shutdown.

Typical repair cost £0-120 (including labour)

DIY fix possible

Check that the filling loop taps are fully closedSwitch off the boiler and allow the system to coolBleed water from a radiator using a bleed key into a containerMonitor the pressure gauge until it returns to between 1.0 and 1.5 bar

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Baxi models that show the E117 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Baxi E117 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 27 April 2026