BoilerFaultCodesWhat the manual says
Manufacturer manualParameter error on parameter storage unit (PSU) or printed circuit board (PCB) – this is a temporary error, the system should reset on its own.
What causes this fault?
This fault occurs when the boiler's internal computer brain momentarily misses a heartbeat while communicating with its memory chip. It is usually caused by a minor electrical interference or a brief data glitch within the electronic control system. In most cases, the boiler identifies the mismatch itself and corrects the data error without any mechanical failure.
DIY fix possible
Wait for the boiler to complete its automatic reset processIf the flashing continues for more than 15 minutes, turn the selector switch to 'Reset' for five secondsMonitor the boiler to see if the lights return to a steady green
Avoid the next call-out bill
A cover plan would handle faults like 5 Green Flashes: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.