BoilerFaultCodesWhat the manual says
Manufacturer manualCentral heating thermostat knob turned off or no heat demand by the eBUS control unit
What causes this fault?
This status occurs because the central heating function has been manually deactivated, often by turning the heating control dial all the way to the left. It signifies that the boiler is intentionally ignoring requests for heating while remaining ready to provide hot water. In some cases, this may also be triggered by an external smart controller or weather compensation sensor telling the boiler that heat is not required.
This is most common during the spring and summer months when homeowners intentionally disable their radiators to save energy.
DIY fix possible
Locate the radiator symbol button or dial on the boiler control panel.Increase the heating temperature setting or turn the dial clockwise.Ensure your room thermostat is turned up to a temperature higher than the current room temperature.
Avoid the next call-out bill
A cover plan would handle faults like S.31: no call-out fees, no surprise bills.
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Related fault codes
All 135 fault codes on the ecoTEC plus 612 R1 VU GB 126/3-5
Seeing a different code? Every code this model can display, in one place.
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