High Lockout
E041 on Vokera Evolve

Your boiler has detected that the water pressure is incorrect or the sensor that monitors it is not communicating properly.

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 – check system water pressure

What causes this fault?

This fault occurs when the boiler's internal sensor detects that there is not enough water pressure to operate safely. The most common reason is a slow leak somewhere in your central heating system or air being released from the radiators, which causes the pressure to drop below the required threshold. It can also be caused by the sensor itself becoming blocked with debris or failing electronically.

This issue often appears in autumn when the heating is turned on for the first time after summer, as natural pressure loss over several months becomes apparent.

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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