Hi,
I wrote in earlier in regards to this same question, how ever I would like to know can I wire the aquastat on the return side of the hydro heating system to the blower unit via, low voltage to the green contact on the blower unit as long as I make the ( Rh &Rc separate on the t- stat, I know that the g contact will be live when the heat calls on the t-stat but I don`t see where this could be a problem as far as a back feed is concerned. Please advise , thanks!

Use a separate relay to activate the blower.

Where Do You Place The Relay Can You Be More Specific, Thanks

It is difficult to do a wiring diagram on the net. May I suggest you surf the net with Google and try to find a wiring diagram for a indoor hot water coil. Many suppliers of HVAC equiptment make them so a diagram should not be hard to find.