High
E2 on Worcester Bosch Greenstar R29 40 HE

Your boiler's internal thermometer is not sending a signal, so the system is shutting down to prevent overheating because it doesn't know how hot the water is.

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

Flow NTC sensor defective. Check flow NTC sensor and connecting lead.

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

E9View →EAView →

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