BoilerFaultCodesYour boiler is working correctly but is currently idle because it hasn't been told to turn on by your thermostat or timer.
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: No heat demand (heating operation)
What causes this fault?
This code appears when the boiler system is functioning correctly but is waiting for a command from your external controls. It physically occurs because the electrical circuit between your thermostat or programmer and the boiler is open, signaling that your home is already at the desired temperature. The most common reasons for this staying on screen when you want heat are depleted thermostat batteries or a programmer set to the 'off' position.
This status is frequently seen during the transition into autumn when homeowners first try to turn their heating back on, only to find their thermostat batteries have died over the summer.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Ensure your central heating programmer or timer is set to an 'ON' period.Check if the batteries in your wireless thermostat need replacing.
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A boiler cover plan would cover faults like S.0 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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