High Lockout
E13 on Potterton Powermax HE

Your boiler’s internal computer has encountered a critical communication error and cannot operate safely.

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 boiler control error

What causes this fault?

This fault occurs when the boiler's main control board suffers a hardware failure and can no longer communicate with the internal sensors. It is usually caused by electrical components on the circuit board wearing out over time or a loose connection in the internal wiring loom. Because the 'brain' of the boiler can no longer monitor safety, it shuts the entire system down as a precaution.

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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