BoilerFaultCodesYour boiler has shut down because it has detected it is getting too hot too quickly, usually caused by poor water circulation or trapped air.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler max temperature exceeded for gradient (probable pump jammed or air in the circuitBoiler max temperature exceeded for overtemperature (probable pump jammed or air in the circuitSafety thermostat sensor tripped.
What causes this fault?
This fault occurs when the water inside the boiler heats up so quickly that the safety sensors shut the system down to prevent damage. The most common cause is a blockage or a failed pump preventing water from moving through the pipes, but it can also be triggered by large air bubbles trapped within the unit.
This issue is more frequent in autumn when heating systems are switched back on after a summer of inactivity, which can cause the internal pump to seize or get stuck.
DIY fix possible
Check that your radiator valves are open and not turned to the off position.Carefully bleed your radiators to remove any trapped air from the system.Restart the boiler by turning the selector switch to the reset position for five seconds.
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Could it be time for a new boiler?
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