BoilerFaultCodesYour boiler is working perfectly fine and is simply in standby mode because your thermostat is not currently asking for the heating to be turned on.
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: Heatingmode:Norequirement
What causes this fault?
This code appears when the boiler has reached its desired temperature or the room thermostat has signaled that the house is warm enough. It is not a fault, but rather the boiler sitting in an idle state to save energy until the temperature drops again. Once the thermostat detects a need for heat, the boiler will automatically restart its firing sequence.
This status is much more frequent during the summer or shoulder months when the heating is turned off or the outdoor temperature is high enough that the thermostat rarely triggers.
DIY fix possible
Check if your room thermostat is turned up higher than the current room temperatureEnsure your heating programmer or timer is set to 'ON'Check that the batteries in your wireless thermostat have not run out
Find a Gas Safe engineer
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A boiler cover plan would cover faults like S.0 — no call-out fees, no surprises.
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