BoilerFaultCodesYour boiler is struggling to light because it is stuck in a cycle of checking for water flow before the ignition process starts.
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's internal computer detects that water isn't moving through the system quickly enough to safely start the burner. It is usually caused by a failing circulation pump that can't push the water round, or a blocked heat exchanger that is restricting the flow. Essentially, the boiler stays in a holding pattern to prevent itself from overheating during the ignition phase.
This issue often surfaces in autumn when the heating is turned back on after a long summer break, as pump components can seize up during periods of inactivity.
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.
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