High Lockout
E042 on Vokera Evolve

Your boiler has lost the ability to measure the water pressure accurately, which has caused it to stop running for safety.

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

Water transducer fault

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring water pressure fails to send a reliable signal to the main control board. The most common cause is a component failure within the transducer itself or a loose connection in the wiring harness. Because the boiler cannot verify if there is enough water to operate safely, it shuts down to prevent internal overheating.

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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