High
d3 on Worcester Bosch R30 HE Plus

Your boiler has stopped working because a safety link inside the unit has either come loose or a connected external safety device has shut the system down.

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.

Technical description

Jumper 155 missing or ST8 (external limiter) has triggered

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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Related fault codes

EAView →A1View →

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