How to check electrical connections & Photocell.
The roller door had developed a problem, and was flashing 4 times repeatedly.
In this video I show how to check the photocell sensor and all the connections to the control panel, also how to reset the ansa panel eventually repairing the system.

Link to Amazon shop for tools, https://www.amazon.co.uk/shop/aaanton11
Link to New control panel, £38, https://amzn.to/2VnVI9X
Link to video on Roller Motor replacement,    • Roller Garage Door Motor replacement,...  

Link to ANSA Door systems website, http://ansadoorsystems.uk