Your boiler has failed to light the burner on start-up and has safely shut down to prevent gas from flowing without a flame.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: lockout (If the boiler has been turned off for some time the first attempt to light it may result in a lockout 4)
DIY fix possible
Locate the Reset button on the front control panel.Press and hold the reset button for 2-3 seconds.Wait for the boiler to cycle through its start-up phase; you may need to repeat this up to three times if the boiler has been off for a long period.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 4 — no call-out fees, no surprises.
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Chaffoteaux System 40 60 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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