Your boiler is temporarily pausing between firing cycles to prevent the system from turning on and off too frequently, which protects the components from unnecessary wear.
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: Service Function: Anti-cycle time
What causes this fault?
This code appears when the boiler has reached its target temperature and needs to wait for the radiators to dissipate heat before firing up again. It is triggered to prevent 'short-cycling,' which happens if the heating system is too small for the boiler's power or if the radiator valves have shut off. By pausing, the boiler protects its components from the mechanical stress of turning on and off too rapidly.
This display is more common in autumn and spring when the weather is mild and the heating system doesn't need to run at full capacity to keep the house warm.
DIY fix possible
Check that all radiator valves are fully open to allow heat to dissipateEnsure the room thermostat is turned up higher than the current room temperatureWait 15-20 minutes for the internal timer to reset and the boiler to restart automatically
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