The boiler is very intermittent when it comes to putting the Rads on, the hot water is fine and has no problems.
The thermostat is working and is sending 240v/240v in and out of the board. When I push the temp up on the thermostat the boiler will try to turn on but fails, however it will turn on when it feels like it..
There is a enough pressure in there cause when it works it works...

Does this sound like a PCB issue ??

Nick, February 2014

Thanks, there is no fault code... :-(

Nick, February 2014

Why not try change heat NTC if might be problem PCB is most expensive item on boiler unless boiler fault code say

ltd, February 2014