BoilerFaultCodes Main burner will not light or lights at low flame (11) High
Your boiler is struggling to detect the demand for hot water or heating because a small internal rubber seal has failed, preventing the system from firing up correctly.
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: Diaphragm split or stretched.
Typical repair cost £180-350 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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
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Chaffoteaux Flexiflame 140 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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