High Lockout
E19 on Potterton Powermax HE

Your boiler's main control board has encountered an internal electronic error and is unable to manage the system 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

Internal control fault

What causes this fault?

This fault occurs when the boiler's internal computer experiences a critical communication failure or a physical degradation of its electronic components. The most common reason is age-related wear to the capacitors and circuits on the main control board, which prevents it from performing vital safety checks.

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

E18View →E20View →E21View →

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