BoilerFaultCodesYour boiler is working correctly but is currently in standby because your thermostat or programmer is not asking 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: Room thermostat 3/4 no heating demand
What causes this fault?
This status occurs when the boiler is waiting for a signal from your thermostat to tell it to turn on. It physically means the electrical circuit between your heating controls and the boiler is open, indicating that your home has already reached the desired temperature. The most common reasons are simply that the thermostat is turned down, the timer is set to 'off', or the thermostat batteries have run out.
This is more frequently queried in autumn when homeowners first turn their heating on and find the boiler doesn't respond because of a programmed schedule or depleted thermostat batteries.
DIY fix possible
Check if your room thermostat is turned up higher than the current room temperature.Ensure your heating programmer or timer is set to 'ON' or 'AUTO'.Replace the batteries in your wireless room thermostat if the screen is blank or showing a low battery symbol.
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A boiler cover plan would cover faults like S.30 — no call-out fees, no surprises.
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