BoilerFaultCodesYour boiler has sensed that the water temperature has risen above the level it was set to reach, leading 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: Current prim. water temp. higher than set val.
What causes this fault?
This fault occurs when the water inside your boiler gets hotter than the temperature you have requested on the control panel. The most common cause is a lack of water flow, which means the heat being produced cannot be carried away into your radiators or hot water cylinder. This is often caused by a failing pump, a blockage in the system, or a buildup of debris inside the main heat exchanger.
This fault is more frequent when the heating is first turned on after summer, as pump components can seize up after long periods of inactivity.
DIY fix possible
Check that all radiator valves are fully open to allow water to circulate.Ensure there is enough water pressure in the system by checking the digital gauge.Restart the boiler using the reset button on the touch screen.
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A boiler cover plan would cover faults like 204 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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