BoilerFaultCodesYour boiler has become too hot and has automatically shut down to prevent damage to the internal components.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check system. Replace o/h stat. Press O/H reset button.
What causes this fault?
This fault occurs when the water temperature inside the boiler exceeds a safe limit, causing the safety sensors to shut the unit down to prevent damage. The most common reasons include a failing system pump that isn't moving water away from the heat exchanger fast enough or a buildup of sludge and debris that has restricted the flow of water.
This fault often occurs during the first few cold days of autumn when a heating system that has been dormant all summer is suddenly forced to work at high capacity.
DIY fix possible
Locate the overheat reset button under the control box flapPress the button firmly to reset the safety thermostatCheck that all radiator valves are open and the system pressure is correct
Find a Gas Safe engineer
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A boiler cover plan would cover faults like OVERHEAT FAULT — no call-out fees, no surprises.
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Ideal Concord CXC 48 116 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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