E9 277 High

Worcester Bosch E9 277 Fault Code

Also written as E9277 — same fault.

The Worcester Bosch E9 277 fault code means: your boiler has shut down because it has detected internal temperatures that are too high, often caused by poor water circulation or a blockage.. It appears on 11 Worcester Bosch models in our database.

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.

Technical description: The safety temperature sensor has measured temperature in excess of 95°c
Typical repair cost £120-£350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Worcester Bosch models that show the E9 277 fault code

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

Source

Worcester Bosch E9 277 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026