How much does it cost to fix Worcester Bosch error code Primary Overheat?

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

Primary Overheat High

Worcester Bosch Primary Overheat Fault Code

Q: What does the Worcester Bosch Primary Overheat fault code mean?

Your boiler has automatically shut down because it has become too hot to operate safely and needs attention to restore central heating or hot water.

Also written as PRIMARYOVERHEAT — same fault.

The Worcester Bosch Primary Overheat fault code means: your boiler has automatically shut down because it has become too hot to operate safely and needs attention to restore central heating or hot water.. It appears on 2 Worcester Bosch models in our database.

Technical description: Boiler not fully water pressurised, air in system, pump failure, primary sensor not correctly fixed to pipe, or short circuit across contacts 5 & 6 (overheat thermostat fault).

Typical repair cost £120-250 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Worcester Bosch models that show the Primary Overheat fault code

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

Source

Worcester Bosch Primary Overheat 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