NO CODE 212 High

Worcester Bosch NO CODE 212 Fault Code

Also written as NOCODE212 — same fault.

The Worcester Bosch NO CODE 212 fault code means: your boiler is shutting down because it is heating up much faster than it should, usually due to water not flowing through the system properly.. 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: Safety or flow temperature rising too fast

What causes the Worcester Bosch NO CODE 212 fault?

This fault occurs when the water inside the boiler heats up too quickly because it isn't being moved away into your radiators or hot taps fast enough. The most common reasons are a pump that has stopped working, a blockage of sludge or limescale in the pipework, or air trapped within the system.

This issue often appears when the heating is first turned back on in autumn, as pumps can seize after being inactive throughout the summer.

Typical repair cost £100-£350 (including labour)

DIY fix possible

Check that your radiator valves are fully openEnsure the central heating system pressure is between 1.0 and 1.5 barBleed all radiators to remove trapped air that might be blocking flow

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Worcester Bosch models that show the NO CODE 212 fault code

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

Source

Worcester Bosch NO CODE 212 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