BoilerFaultCodesYour boiler is working normally and is currently heating up your radiators.
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: Boiler in heating mode
What causes this fault?
This is a normal operational status and not a mechanical fault or failure. It appears when your thermostat or programmer has requested warmth, signaling the boiler to ignite the burner and circulate hot water to your radiators. You may see this code frequently during colder periods as the system works to maintain your target indoor temperature.
You will see this code more regularly during the autumn and winter months when your central heating is scheduled to be 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 200 O — no call-out fees, no surprises.
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