I have a Glow worm Micron 40FF boiler with a Drayton Tempus 7 controller on a central heating system with a diverter valve and a cylinder stat. I wish to check that the system is wired up correctly as I have an intermittent fault that puts the boiler into reset mode, when the central heating is on timed for twice a day operation. I was also led to beleive that it had hot water priority, but looking at the internal wiring of the Tempus 7 controller I can not see how this can operate. Is there anything I need to add to my system to give me this or will I need a different controller?