How much does it cost to fix Worcester Bosch error code 9.E?

Typical repair cost for the Worcester Bosch 9.E fault is £120-£250 including labour.

9.E High

Worcester Bosch 9.E Fault Code

Q: What does the Worcester Bosch 9.E fault code mean?

Your boiler is struggling to detect when you turn on a hot tap, meaning you might have inconsistent or no hot water.

Also written as 9E — same fault.

The Worcester Bosch 9.E fault code means: your boiler is struggling to detect when you turn on a hot tap, meaning you might have inconsistent or no hot water.. It appears on 1 Worcester Bosch model in our database.

Technical description: Turbine signal delay (combi only)

What causes the Worcester Bosch 9.E fault?

This fault occurs when the boiler's internal sensor fails to detect water moving through the system quickly enough after you open a tap. It is usually caused by a sticking flow turbine that can't spin freely or a failing diverter valve that is struggling to switch the water flow from heating to hot water mode.

Typical repair cost £120-£250 (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 9.E fault code

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

Greenstar CDi Compact Repair: £120-£250

Source

Worcester Bosch 9.E 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