Low
376 E4 on Worcester Bosch Greenstar CDi Compact

Your boiler is having trouble sensing the temperature of the incoming cold water, which may prevent the preheat function from working correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Preheat sensor on DHW Inlet Open Circuit

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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