D4213 High

Worcester Bosch D4213 Fault Code

The Worcester Bosch D4213 fault code means: your boiler is heating up too quickly, which usually means the water inside is not circulating properly or the system is low on pressure.. It appears on 1 Worcester Bosch model 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 actual temperature recorded by the flow temperature sensor or return temperature sensor is rising too quickly

What causes the Worcester Bosch D4213 fault?

This fault occurs when the heat exchanger gets too hot too quickly because water isn't moving away from it fast enough. The most common reasons are a failing circulation pump, a blockage in the pipework, or air trapped within the system preventing the flow of water.

This issue often surfaces in autumn when the heating is turned back on after a long summer break, as internal pump components can seize during periods of inactivity.

Typical repair cost £120-280 (including labour)

DIY fix possible

Check the system pressure gauge and top it up to 1.5 bar if it is too lowEnsure all radiator valves are fully open to allow water to flowBleed all radiators to remove trapped air that might be blocking circulation

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Worcester Bosch models that show the D4213 fault code

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

Source

Worcester Bosch D4213 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