High
OVERHEAT on Johnson Starley Warmcair DW

Your boiler has become too hot and has automatically shut 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

Appliance requires cooling down. Includes checks for overheat sensor, service valve positions, water levels, and air in the system.

From this model's manual
Verified against the Johnson Starley Warmcair Dw 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.

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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