High Lockout
E153 on Potterton Gold Combi HE

Your boiler's computer has temporarily locked itself because the reset button was pressed too many times in a short period.

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 board error / Reset button pressed too many times

What causes this fault?

This fault occurs when the boiler's internal computer registers too many reset attempts within a five-minute window, causing it to freeze for luxury and safety reasons. It is usually triggered by a homeowner trying to clear a different, underlying fault code repeatedly without fixing the actual problem. The boiler essentially enters a 'timed lockout' to protect the electronic components from further interference.

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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