BoilerFaultCodesYour boiler is working normally and is currently heating up your hot water.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: DHWmode:Burneron
What causes this fault?
This is actually not a fault, but a status code indicating that your boiler is currently firing to heat your tap water. It appears when someone turns on a hot tap or if the boiler is pre-heating its internal tank to ensure hot water is ready when you need it. Once the demand for hot water stops, this code will naturally change to a different status.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like S.24 — no call-out fees, no surprises.
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