BoilerFaultCodesYour boiler is working fine, but your external room thermostat or timer is telling it not to turn the heating on right now.
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: Roomthermostatisblockingheatingmode.
What causes this fault?
This code occurs when the boiler is technically ready to provide heat, but it hasn't received a signal from your external controls to start. The most common reason is that your room thermostat is set lower than the current room temperature or has run out of batteries. It essentially means the boiler is 'on standby' waiting for your timer or thermostat to tell it that the house is cold.
This is frequently reported during the first cold spell of autumn when homeowners forget to replace thermostat batteries or adjust summer timers.
DIY fix possible
Check that 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 wall thermostat if the screen is blank or showing a low battery symbol.
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