BoilerFaultCodesYour boiler has likely overheated or has an issue with its internal fan system, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: High limit thermostat or air flow switch fault
What causes this fault?
This fault occurs when the boiler's internal components detect that the unit is either getting too hot or that the fan isn't safely clearing waste gases. The most common reasons are a blockage in the flue, a failing circulation pump, or a simple mechanical failure of the safety sensors themselves.
DIY fix possible
Turn the mode selector switch to 'OFF/RESET' for a few seconds.Move the switch back to either 'Hot Water' or 'Heating and Hot Water' mode.Check that all radiator valves are open and your wireless thermostat has working batteries.
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 RED LED BLINKS — no call-out fees, no surprises.
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Vokera Compact HE 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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