After some careful consideration, I think I'm going to use a vertical bore instead of digging up a big chunk of my yard. I contacted a local driller and have a quote for twin 230ft bores filled with "enhanced" grout. The HP will be a 3 ton unit and I will have a propane fireplace in the finished basement as aux heat when it gets nasty cold. OK>> On to my question I asked for the driller to quote the job having both supply and return lines from each bore run into my basement without a header. I'd like to be able to monitor each bore independently and flush-maintain them individually instead of never knowing if one bore is working better than the other. I'm also thinking that it might make sense to only use one bore during light load times to reduce pumping requirements. My goal is to have very few connections outside the basement and the maximum flexibility for monitoring and troubleshooting. The driller seems reluctant to this and I'm not sure why. I'm hoping that "they just never do it that way" I also want him to simply bore the holes and install the tube/grout. I want to handle the penetration into the house, fill, flush, test, etc once I get the system ready to run. I know this is a bit out of the ordinary, but no-one EVER said I was ordinary!