4 High
Your boiler has tried to light but cannot detect a flame, meaning it has shut down as a safety precaution.
Technical description: No flame signal
Typical repair cost: £100-£350 (including labour)
DIY fix possible
Check that your gas emergency control valve is in the open positionIf you have a prepayment meter, ensure you have credit and the meter is activeCheck if other gas appliances, such as a hob, are working to confirm gas supplyReset the boiler by pressing the reset button for 2-3 seconds
Protect yourself from future repair bills
A boiler cover plan would cover faults like 4 — no call-out fees, no surprises.
*Affiliate links — we may earn a commission at no extra cost to you. Prices shown are starting prices.
Parts commonly replaced
- Ignition electrode
- Ionisation probe
- Gas valve
- PCB
*Affiliate links — we may earn a commission at no extra cost to you.