Medium Warning
E54 on Baxi EcoBlue Heat

The boiler is struggling to detect when you turn on a hot tap, which may result in lukewarm water or no hot water at all.

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

Domestic hot water (DHW) flow sensor fault

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring water movement fails to tell the boiler that you have opened a tap. The most common reason is that the small internal turbine has become jammed with limescale or debris, preventing it from spinning and sending a signal. In some cases, the electrical connections between this sensor and the main control board may have become loose or damaged.

Engineer required

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

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