BoilerFaultCodesYour boiler has stopped working because water is not moving through it properly or there is trapped air causing it to overheat.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Exchanger protection activation – no system circulation air in system
What causes this fault?
This fault occurs when the boiler detects that heat is not being carried away from the heat exchanger fast enough, causing it to reach a dangerously high temperature. The most common reasons are a failed pump that isn't pushing water around, or a buildup of air and sludge that is blocking the flow within the pipes.
This issue is more frequent in autumn when heating systems are switched back on after a summer of inactivity, which can cause internal pump components to seize.
DIY fix possible
Check that your system pressure is between 1 and 1.5 bar on the pressure gaugeBleed all radiators in your home to remove trapped airEnsure all radiator valves and external isolation valves are fully open
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F43 — no call-out fees, no surprises.
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Ferroli Modena 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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