Yes this was with the old setup. The boiler itself has a thermostat on it too which is why I think it was switching on and off without the pumps being on.
Thanks Tony,
If I connect the boiler directly to the mains it comes on straight away. I am guessing once the boiler thermostat kicks in it will switch off until one of the pumps starts. Does this sound right?
Firstly, sorry if the terminology is wrong I'm a PC engineer not heating engineer.
Just had a new Honeywell ST9400Ccontroller fitted to my Potterton Statesman (not Flowsure) based CH / HW system to replace an old clockwork one. As it was an insurance job it wasn't my usual service engineer...