High Lockout
E 36 on Vokera Hydra

Your boiler has lost the ability to detect the flow of water, so it has shut down to prevent damage from overheating.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Open circuit on flow sensor

What causes this fault?

This fault occurs when the boiler's internal computer can no longer detect a signal from the sensor that monitors the temperature of the water leaving the heat exchanger. It is usually caused by the sensor failing internally or a loose connection in the wiring that links the sensor to the main control board.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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