BoilerFaultCodesYour boiler is working perfectly fine and is simply waiting for you to turn up the thermostat or turn on a hot tap.
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: Standby, no demand for heat present.
What causes this fault?
This status occurs when the boiler is powered on and ready to work but hasn't received a signal to start heating. It means your thermostat is currently set lower than the room temperature, or no one has turned on a hot water tap yet. As soon as you request heat, the code will change and the boiler will fire up.
This code is more frequently seen in the summer months when the central heating is turned off and the boiler only wakes up for occasional hot water use.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperatureEnsure your heating programmer or timer is set to 'On'Turn on a hot water tap to see if the code changes to 'd' or 't'
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