Trianco Eurostar Eco Combi 90. Hot water, no heating

[Swaddy]

Hi all,
I've just joined as there seems to be a great deal of sense talked on DIYnot as opposed to elsewhere on the tinterweb.

I am hoping for some assistance with a heating problem with my Trianco Eurostar Eco Combi 90 oil fired boiler.
The hot water works fine but there is no fire up on demand for the central heating.
I have gone through the basics,
a) Demand is on programmer
b) Room stat is calling for heat
c) Room stat is working (tested)
d) Replaced the CH control thermostat (206896 - KP36 1330)
e) 3 way diverter valve is working (brand new)
f) Motorised (syncro) valve is working (tested)
e) HW control thermostat has continuity acros electrical spade terminals after initial "click"...is this right?

Might be a coincidence but just before the CH packed up, the HW was VERY hot.

Any help would be very much appreciated.

Here's hoping!!

 

[Swaddy]

What a numpty!! All solved, I had crossed over the white and orange wires between the tank thermostat and the boiler limit stat (must have been when I changed the CH Control stat).
Lesson learned, check, check and check again.

Thanks all.

Swaddy