BoilerFaultCodesYour boiler is currently restricted to a lower power setting for heating, meaning your radiators might take longer to warm up or may not get as hot as they should.
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: Heating part load error
What causes this fault?
This occurs when the boiler's software has been manually adjusted to limit how much gas it uses for the heating system. It is usually set by an engineer during installation to match the size of your home, or it may have been limited accidentally during a service. Because of this limit, the boiler cannot use its full power to heat your radiators even if the house feels cold.
This issue is most noticeable during the first cold snap of winter when the boiler's restricted power output struggles to keep up with the dropping outside temperatures.
DIY fix possible
Check if any radiator valves are turned off or restrictedMonitor if the home reaches the desired temperature over a longer periodNo immediate action is required if your home remains comfortable
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A boiler cover plan would cover faults like D.0 — no call-out fees, no surprises.
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