In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
I am renovating an old house and installing floor radiant heat to replace a hot air system. I'm afraid I didn't do enough front end research when I bought into a system design by Mr. Seton from the Radiant Design institute. I've attached a diagram of the Indirect system w/ DHW he provided. I have purchased all the materials he listed to complete the system.
I've finished installing the pex tubing; four loops of staple-up and three loops in concrete in the addition. I'm ready to plumb the manifold/heat exchanger/heater and thought I would model it on the 'Thermal Transfer Station' and 'Manifold Assemblies' he sells. (http://www.heatingmanifolds.com/page3.html, http://www.heatingmanifolds.com/page2.html)
After noting that his HX is not plumbed for counter-flow as recommended, I began to do more research and am worried about the effectiveness of the system as designed.
So, some specific questions on plumbing
On the manifold side, is the Expansion Tank plumbed right:- am I pumping away from it if the HX is between it and the pump, and shouldn't it come off an Air Eliminator?
On the heater side, am I pumping away from the check valve?
Will I need to add mixing valve(s) for DHW and the different pex loops (Fred never indicated or answered my question about the design temp for the loops)
Is a check valve needed where the cold supply meets the return from the HX and tees to the heater inlet?
Do the Taco 008 pumps have or require check valves?
I've done irrigation and house plumbing, and the radiant heating seemed straightforward until I started looking at it in more depth. Any advice or suggestions on additional components needed for finishing this system correctly would be greatly appreciated.