BoilerFaultCodesYour boiler is simply letting you know that your external smart thermostat or system controller has successfully requested 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: Hot water activation via ebus control
What causes this fault?
This code appears when your external smart thermostat or system controller sends a digital signal to the boiler asking it to heat your hot water cylinder. It is not a malfunction, but rather a status update showing that the communication between your controls and the boiler is working correctly. You will typically see this on the screen whenever your programmed hot water schedule is active.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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A boiler cover plan would cover faults like D.25 — no call-out fees, no surprises.
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