High
54 on Worcester Bosch WR325 RSF

Your boiler has reached an unsafe temperature and has shut itself down to prevent damage to the internal components.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Overheating

From this model's manual
Verified against the Worcester Bosch Wr325 Rsf installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when water cannot circulate through the boiler quickly enough to carry heat away, causing the internal temperature to spike. The most common reasons are a failed pump that isn't pushing water, a blockage caused by sludge buildup, or air trapped within the system.

This issue is more frequent when heating is first turned on after summer, as the pump can seize up during long periods of inactivity.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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