Your boiler is working correctly and is currently in standby mode because your thermostat or timer is not telling it to provide any heat.
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 heating required
What causes this fault?
This code appears when the boiler is patiently waiting for a command from your room thermostat or programmer. It means the water inside the boiler has already reached the required temperature, or your heating controls are currently set to 'off' because the house is warm enough. The boiler hasn't broken down; it is simply sitting in standby mode to save energy.
This is very common in summer or during warm spells when your thermostat reaches its target temperature quickly and stops asking the boiler for heat.
DIY fix possible
Check that your room thermostat is turned up high enough to trigger the heating.Verify that your heating programmer or timer is set to an 'ON' period.Ensure that any thermostatic radiator valves in the house are turned up.
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