BoilerFaultCodes Lockout High
Your boiler has stopped working because it failed to light or stay lit, and it needs a manual restart to try again.
Call an engineer soon
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Lockout / flame failure (Red indicator 24 lights). Possible causes include the boiler being turned off for some time. Requires manual reset using the reset button (25).
Typical repair cost £100-250 (including labour)
DIY fix possible
Locate the reset button (marked 25 on your control panel).Press and hold the reset button for 2-3 seconds.Wait to see if the boiler ignites and the red light stops flashing.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Lockout — no call-out fees, no surprises.
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Chaffoteaux 80/100 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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