BoilerFaultCodesYour boiler is currently struggling to light the flame needed to provide you with heating and hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: ignition
What causes this fault?
This fault occurs when the boiler attempts to light the burner but fails to detect a stable flame after several tries. The most common reasons are a worn-out ignition probe that can no longer create a spark or a blockage in the gas supply preventing fuel from reaching the burner.
This issue often surfaces during the first cold snap of autumn when the boiler is forced to work harder after sitting idle throughout the summer.
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
A boiler cover plan would cover faults like S.03 — no call-out fees, no surprises.
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