BoilerFaultCodesYour boiler is currently set to run at a lower power level than its maximum capacity to save energy or match your home's heat demand.
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: Partial heat load (Diagnostics menu)
What causes this fault?
This status appears because the boiler’s maximum output has been manually limited during installation or a service to better suit the size of your property. It is not a mechanical failure, but rather a configuration setting that ensures the unit doesn't use more gas than necessary to heat your radiators. It prevents the system from 'short cycling,' which occurs when a boiler is too powerful for the home it is heating.
DIY fix possible
Press the 'Menu' button on the control panelNavigate to the diagnostics settings (D.00) using the +/- buttonsReview if the output kW matches your home's requirements, but usually, this setting should be left to a professional during installation
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A boiler cover plan would cover faults like D.000 — no call-out fees, no surprises.
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