Thanks for the replies but I think there are may be some cross wires here so i’ll try and keep it simple:
I have a combination boiler supplying one 8 port manifold UFH with augmenting pump. (no rads, one central room stat.)
Bought FW100 as this was also a programmable timer and room stat...
Why can't I connect into the timer I have, why do I need to buy another timer?
If you know something I don't I would love to hear from you as I can't see any way around this.
My system is: one large zone of UFH, no rads.
I found your post when I was googling what the FW100 was selling for on ebay.
I had to laugh because I think I may have exactly the same issue as you.
I have been trying to connect in an additional ‘240v supply’ argument pump for the UFH to the low voltage FW100 but this can’t be done...