BoilerFaultCodesYour boiler is providing central heating as normal, but the system is failing to detect when you turn on a hot tap.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Heating but no hot water
What causes this fault?
This fault occurs when a component inside the boiler fails to sense that you have turned on a hot tap, meaning it doesn't know to switch from heating mode to hot water mode. The most common reason is a perished rubber diaphragm or a stuck flow switch that creates a physical disconnect between the water moving and the boiler's electronics. In some cases, the diverter valve may be mechanically seized, preventing the internal flap from moving into the correct position.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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