High Lockout
46E on Ravenheat HE 80/90 / 25-30s

Your boiler has detected a problem with the sensor that monitors internal water pressure, meaning it cannot confirm if there is enough water to operate safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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 pressure sensor error, could be open or short

What causes this fault?

This fault occurs when the boiler's control board loses communication with the sensor that monitors water levels inside the system. It is usually caused by a physical failure of the sensor's internal components, loose or corroded electrical connections, or a malfunction in the main control board itself.

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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Related fault codes

10EView →

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