High
A LED 2 on Ferroli Optima 201

Your boiler is failing to detect that you have turned on a hot water tap, so it is choosing not to heat the water for your shower or kitchen taps.

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

D.H.W. flowmeter (136) not operating.

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

A01View →

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