BoilerFaultCodesYour boiler is working perfectly; it is simply in standby mode because your thermostat hasn't asked it to turn on for heating or hot water yet.
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: No heat required
What causes this fault?
This code appears when the boiler is powered on and ready to work, but your thermostat or timer is not currently asking for heat. It signifies that the internal sensors have confirmed all systems are safe and the unit is simply waiting for a signal to start the burner. Once you turn up your heating or trigger a hot water demand, this code will automatically change as the boiler fires up.
This status is most frequently seen during the summer months or warmer shoulder seasons when your central heating is turned off and the boiler is only waiting for occasional hot water demands.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Verify that your heating programmer or timer is set to 'ON'.Ensure the thermostatic radiator valves (TRVs) in your rooms are turned up.
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A boiler cover plan would cover faults like S.0 — no call-out fees, no surprises.
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