High
T2 on Worcester Bosch Heatslave

Your boiler's internal fan is failing to start correctly, meaning the system cannot safely clear exhaust fumes and will not fire up.

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

Fan test – checking the basic fan

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

T1View →T3View →T6View →

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