If the header tank is on the ground floor then no, as the F&E tank
has to be
higher than the rads. If the header tank can be higher than the
boiler, get
an open vented "heating boiler", and use a plate heat exchanger off
the
BoilerMate for the CH, which will get the rads over the header tank.
Only
the CH circuit on one side of the plate will be pressurised.


Sorry, I didn't make it very clear. I think I can get the F&E tank
higher than all the rads now, so I could easily have the whole system
OV.

In this case, I don't need the heat exchanger and can connect it
exactly as it is at the moment (with a larger boiler) or I could take
the CH off the Boilermate and feed it seperately (which would give me
the whole store for DHW).

Which do you think would be best?