High
338 F0 on Worcester Bosch Greenstar CDi Compact

Your boiler is repeatedly trying to start up its flame but failing to detect that water is circulating through the system, causing it to lock itself to prevent damage.

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

Too many short burner starts without confirmation of water flow

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

338View →EAView →F0View →

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