Low
S.30 on Vaillant Atmomax

Your thermostat has told the boiler not to turn on the heating, likely because it is set too low or has lost connection.

Monitor it

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 is blocking heating mode

DIY fix possible

Check that your room thermostat is set to a temperature higher than the current room temperature.Replace the batteries in your wireless thermostat or programmer if they are low.Ensure the timer or heating schedule on your central heating controls is set to 'On' or 'Auto'.

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