Low
LED 2 yellow (1) [CH mode] on Ferroli Optima 201

Your boiler has correctly sensed that a hot water tap is running, and this light simply signifies that it is currently preparing to heat your water.

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

Hot water tap open - D.H.W. flow switch (38) contact closed

Engineer required

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

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