Medium Lockout
AL60 on Vokera Syntesi 29

Your boiler is having trouble measuring the temperature of your hot water, which usually means your taps will only run cold.

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

DHW sensor fault

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring the temperature of your tap water stops sending a clear signal to the main control board. The most common reason is that the sensor has physically degraded or developed an electrical short, preventing the boiler from knowing how hot the water is. As a safety precaution, the boiler will stop heating your water to prevent it from reaching dangerous temperatures.

Engineer required

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

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