Hi there
Basin tap - Armitage Shanks Sensorflow Solo S8135AA-sensorflow-tap.jpg

I have a few of these taps at work and one is very intermittent and sometimes comes on on its own. I have taken the cover off the control box and there is a green led flashing away. The red one comes on when the solenoid valve clicks on. Quite often I can put my hand near the sensor and nothing happens, the green led still flashes but the red led doesn't come on. Do I need a new tap or just the control box. Is there any other fault finding I can try ?

Thanks