2965 B High

Worcester Bosch 2965 B Fault Code

Also written as 2965B — same fault.

The Worcester Bosch 2965 B fault code means: your boiler has shut down because the water inside is getting much hotter than it should be, which is often caused by a blockage or a pump failure preventing the heat from moving away.. It appears on 14 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: Flow temperature too high

What causes the Worcester Bosch 2965 B fault?

This fault happens when the water leaving the boiler heats up too quickly or exceeds safe limits, causing the system to shut down for safety. It is usually caused by a pump failure or a blockage within the pipes that prevents hot water from circulating away from the boiler's heat exchanger. In many cases, it is the result of 'sludge' or debris building up over time and restricting the flow of water.

This fault is most common during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause internal pump parts to seize.

Typical repair cost £120-£350 (including labour)

DIY fix possible

Check that all radiator valves are fully open to allow water to circulate.Ensure your boiler pressure gauge is between 1 and 1.5 bar; top up if necessary.Check if any external bypass valves or magnetic system filters are blocked.

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Worcester Bosch models that show the 2965 B fault code

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

Source

Worcester Bosch 2965 B 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