No pm's only chatting to people and reading. Was told to check a few things viz when wiring a 2 port valve the neon light is useful indicator to know when it is in open position as it aids the wiring process. MYSON have this.
The upshot is the valve in hot press does work but only in 2 ways, opens when hot water called for but will not close with hot tank thermostat, this means either stat on hot tank faulty or valve faulty! Then motor valve on in hot press tank closes when I switch on heating.
By fiddling with valve in BH and accepting that valve in Hot Press is opening and closing then system is ok. The fault I had was heating would not go off at all, cause was the sticking valve in BH and then when I wanted HW the solo rads were getting warm, cause valve in BH sticking so hot water getting into CH flow.
To sum up I was told 2 valves in BH and HP needed replacing, stat for hot tank could be faulty!! It so happens the valve in HP was a RANGE model ie sunvic and a google brought up interesting reading. The system I have is not complex, all I wanted was with HW on the stat on hot tank would turn off system when required temp reached, and when heating on the wall stat would turn on and off CH at the set temperature. It never worked properly so I got round it by timing hot water ie on for 1 hour.
Its ok now and had CH and HW on, its possible valve in BH will slip again but I am aware. I'll never know if valve in HP ever worked or if it is faulty as electrician who was out can blame it or the tank stat. I have given up but I now have a lot more knowledge than when I started. MYSON and HONEYWELL appear to be favoured.
noah