BoilerFaultCodes.com
Blue light: On, Lockout reset: Off (Alt 2) Medium Warning

Your boiler is providing central heating but is failing to detect when you turn on a hot water tap.

Book a service

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: Boiler not operating during hot water demand (CH ok)

What causes this fault?

This fault occurs when the boiler's internal sensors fail to detect that water is moving through the pipes when you open a tap. The most common reason is a faulty turbine sensor that has stopped spinning or an electronic component that is failing to relay the request for heat to the main control board.

Typical repair cost £140-£220 (including labour)

Engineer required

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

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Protect yourself from future repair bills

A boiler cover plan would cover faults like Blue light: On, Lockout reset: Off (Alt 2) — no call-out fees, no surprises.

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