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

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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Ferroli Boiler Optima 201 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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Boiler cover options

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