Ladia,
That explains why your system is more complicated than mine. Again, mine is strictly forced air heat & cool, with the super deheater heating the hot water. I have pex tubing in the entire basement floor, in 6" of suspended concrete in the kitchen, and 3" suspended concrete in the master bath, but none of it is hooked up yet. I have not figured an easy way to use the geo system to warm these floors, since I am pretty much using all of the hot water the system produces for domestic. In fact, my electric bill stayed the same last fall when we quit using the A/C. The electric water heater had to take over. I might as well keep running the A/C.
I am thinking of just using a small water heater and pump to circulate 90 - 100 degree water through these floors. It won't be so much to heat the house, just enough to take the chill off the tile floors.
As you mentioned earlier, with radiant heat, especially in concrete, you can't just decide to raise the temperature because you are chilly. It takes several hours to make an adjustment, both up and down. Does your system look at the temperature and trend outside to decide that it's time to start (or stop) warming the floors? I don't know if I will need this or not, but it is something I would like to learn more about.
