So there was only a projected $500/yr savings before installer decided to upsize system? Yikes.
What size is your duct work.

All,
Thank you for the input back in Feb. I have been working the installer and then Bryant hard with the information/education you provided. After months of delay, and denial on installers part and slow reaction on Bryants part, with persistance I finally gained their attention.

Installer admitted last week that loop trench length of approximately 700 feet is too short of 50YD 072 he installed. He is supposed to come see me Friday with two options. He alluded that Bryant wants to install a 4 ton unit in place of what I have OR add another 200 foot trench.

If I change to a 4 ton...is that big enough for a heat load of 80000 (which is what I think it is now)? Is 700 feet of trench enough for a 4 ton? If I keep 50YD 072 and add another trench, if they do the 2 pipe, 6 feet deep, I'd only add 200 feet of trench (because the other 4 trenches range in length from 160 feet to 185 feet to reach almost 700 feet total). So is 900 feet going to be enough. I'll be going over GeoDesigners with installer Friday, but would like your wise thoughts before then.

THANKS!
Sam

I dunno Sam, without re reading everything, you seem to have missed the part where multiple pro's told you EWT of 35 was okay. Did it get lower? How much?

If you are you planning on having Aux heat provide part of the load, then going with a smaller heatpump will help your loop.