BoilerFaultCodesYour boiler has detected a general internal fault that could be caused by anything from low water pressure to the unit overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty boiler or irregular operation as: Empty primary circuit, No primary circuit flow, Lack of burner ignition, Excessive temperature in the primary circuit, Dip-switch 3 left in the OFF position, or Faulty temperature probe
What causes this fault?
This fault occurs when the boiler's internal sensors detect that water is either not moving correctly through the system or has reached a dangerously high temperature. It is often triggered by a lack of water pressure, a blockage in the pipes, or a failing pump that can no longer circulate heat away from the burner.
This issue frequently appears during the first cold spell of autumn when heating systems are turned back on after sitting idle, which can cause internal pumps to seize.
DIY fix possible
Check that the pressure gauge is between 1 and 1.5 barTop up the water level using the filling loop if the pressure is too lowEnsure all radiator valves are open to allow water to flowRestart the boiler by turning the control knob to 'Reset' and then back to the desired setting
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A boiler cover plan would cover faults like Very fast pulses (4 per second) — no call-out fees, no surprises.
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Ideal Mini is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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