How to wire Geothermal heat pump to Air Handler

Hi

I have a 5 ton waterfurnace in the basement of out house.In the past few years we only used it to heat our house (Infloor heating). This year I finally got around to set a 5 ton trane air handler in the attic and connect it to the duct work. Now I am a little in the dark on how to "connect" the Heatpump with the air handler elcetrically?
Do I run all through one thermostat or what do I have to do in order to allow the heatpump and the circulation pumps for the cold water to start up when the air handler is needed? Can any body send me a link to a good wiring diagram?

Thanks so much.

TR