Excuse the colours of the cables they are not correct. I have a Potterton controller that is wired like below and I need to convert to nest. I can get the boiler on and the heat link up. But there no response for a call for heat or water. Can anyone give me some pointers or a diagram that should work? I know I need to take the existing thermostat out but I'm not sure what C is doing? Also not sure why there's a jumper between L and 5, but without the boiler is off..
