Neil, looking good..
For those of us stumbling down this same road, what are the hose & fitting sizes you were able to get on the installed HX? I know we've discussed some data offline that you thought at least 1/2" NPT as the minimum (I've had plenty of success locating reasonably priced HX's with 3/8" NPT
) - but I also know you have the out-of-the-ordinary hot water loop in yours too. So, I was just curious what yours ended up being...hard to tell from the pics since there isn't really a good frame of reference.
My current thought is that I'd like to go 1/2" NPT & 5/8" hose wherever possible.