BoilerFaultCodesYour boiler has detected that water is not moving through the system properly or there isn't enough water inside the unit to safely heat up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Circulation error or dry fire
What causes this fault?
This fault occurs when the boiler's internal sensors detect that heat isn't being carried away from the heat exchanger quickly enough, usually due to a lack of water flow. The most common reasons are a failed circulation pump that can no longer push water through the radiators, or a blockage such as a build-up of sludge or air in the pipework.
This issue is frequently seen in autumn when heating systems are turned back on after a long summer break, as pumps can often seize up during periods of inactivity.
DIY fix possible
Check that your external heating system pressure is between 1 and 1.5 barEnsure all radiator valves and isolation valves are fully openGently bleed your radiators to remove any trapped air pockets
Find a Gas Safe engineer
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A boiler cover plan would cover faults like ON FLASH FLASH — no call-out fees, no surprises.
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Baxi Solo 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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