Hi all, I found this site researching geothermal systems. I have a 20 year old A/C and nat gas furnace that needs replacing, so I'm working to educate myself on the options. My location is near Cincinnati. House is 2500 sqft in the top 2 floors, and another 1000 sq ft of finished space in a partially finished basement. I was quoted a complete Bryant/Carrier 4-ton geothermal system with horizontal layout for $15,000. Installer said he would make 450' of trench, and use a 6-pipe configuration. The trench would be 4' wide and 6' deep. He claims 100' of 6-pipe configuration yields 1-ton of capacity...and that he adds 50ft to that "just to be safe". The 6 pipes would be 3/4" pipe, the main pipe would be 1-1/4". Does this make sense? Based on what I've read, it seems woefully short on capacity...though I haven't seen a lot of 6-pipe installations discussed. That being said, the guy is experienced with several good references. Thanks in advance for any help!