BoilerFaultCodesYour boiler has lost its flame while running, which means it has safely shut down to prevent issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame error
What causes this fault?
This fault occurs when the boiler's control system loses the signal that a flame is present while it should be firing. It is often caused by a buildup of carbon on the electrodes or a blockage in the condensate trap that backs up and 'drowns' the flame. In some cases, it can also be triggered by an inconsistent gas supply or a failing gas valve that cannot maintain a steady flow.
This fault is more common during extreme cold spells, as a frozen external condensate pipe can cause water to back up into the boiler and extinguish the flame.
DIY fix possible
Check if other gas appliances, like a hob, are working to confirm gas supplyEnsure your pre-pay gas meter has sufficient creditPress and hold the Reset button for five seconds
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 E128 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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