Medium
Failure at point L on Worcester Bosch 24CDi BF

Your boiler is struggling to keep your hot water at a consistent, safe temperature, meaning it may fluctuate between being too hot or too cold.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Domestic hot water temperature does not stabilise at 55-60°C. Involves checking Modureg DC voltage and domestic hot water sensor resistance (1.5 to 25 kohms).

Engineer required

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

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