10 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Genus ONE
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Your boiler's burner keeps shutting off while you are trying to run hot water, meaning your taps might go cold.
When you run the hot water tap, your radiators are getting warm instead of just heating your water.
Your boiler is struggling to keep your hot water warm enough while you are running the taps.
Your boiler is making unusual noises and struggling to provide hot water properly, usually due to limescale buildup or low water pressure inside the system.
Your boiler has detected an incorrect water pressure level in the heating system, which usually means it needs more water added or has a minor leak.
Your boiler keeps safely shutting down because it is struggling to reliably detect the burner flame.
Your boiler has automatically shut down because it detected that the internal water is getting dangerously hot, which usually points to poor water flow or trapped air.
Your boiler temporarily fires up when you turn off a hot water tap due to a sudden pressure drop in your home's water supply.
Your boiler has noticed that the water circulating through your radiators is not getting as warm as it should.
Your boiler has automatically shut down because it has detected dangerously high internal temperatures.
BoilerFaultCodes