High Lockout
0E13 on Alpha Pro Tec Plus

Your boiler has locked itself for safety after too many unsuccessful restart attempts in a short period of time.

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

Maximum number of resets reached. More than five reset attempts have been reached within 15 minutes.

What causes this fault?

This fault occurs when the boiler's safety software detects too many manual reset attempts in a 15-minute window and enters a protective lockout. It is usually triggered because an underlying issue caused the boiler to fail initially, leading the user to repeatedly press the reset button. The boiler essentially stops responding to prevent potential damage or further safety risks from constant restarting.

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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