BoilerFaultCodes Main burner will not light or lights at low flame High
Your boiler is failing to ignite the main flame, which means it cannot heat your home or provide hot water.
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: 1. Electricity not switched on. 2. Fuses missing or blown in control box. 3. Boiler thermostat at low setting. 4. Boiler thermostat faulty or not plugged into control box. 5. Gas supply insufficient. 6. Lack of water in system. 7. Air in system. 8. Boiler pump faulty. 9. Water filter in return pipe blocked or high pressure and balancing tubes blocked. 10. Bearing plate spindle bent or dry. 11. Diaphragm split or stretched. 12. Heat exchanger blocked.
Typical repair cost £150-£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?
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