BoilerFaultCodesTechnical description
No heat demand boiler in summer operating mode
What causes this fault?
This code appears when the boiler's internal settings have been adjusted to keep the central heating turned off, usually via the control dial or digital menu. While the unit will still provide hot water for your taps, it is intentionally ignoring any signals from your thermostat to warm up the radiators. It is often triggered accidentally when someone tries to turn the heating down and inadvertently switches the system into a 'hot water only' mode.
This is very common in early autumn when homeowners forget they switched the boiler to summer mode several months prior and try to turn the heating back on for the first time.
DIY fix possible
Locate the radiator symbol button or dial on the boiler control panelIncrease the heating temperature setting above 0 or 'Off' until a temperature appearsCheck that your room thermostat is turned up higher than the current room temperature