Let me start out by saying I am by no means an expert here. I'm still learning as I go. Most of the stuff I learned about OWB's was from the 'net and this site, but I think your design looks good.
I'm not sure why I drew those lines white in my drawing... it was a long time ago, but they happen to be a mixture of copper and PEX. I think I have 1" lines everywhere except for my floor lines which are 1/2"
I would have the floor loop after the HX so that the hottest water is running through your furnace, and it will get a little cooled down by it. That way you won't have super hot water running through your floor lines. That's what the mixing valve is for I think, to cool down the floor lines a bit.
As far as needing a manifold, you don't really need one since you're only adding one loop, although if it was at all possible to add loops in the future, you may want to add one.
The valves I have in there are for servicing and stuff, being able to shut one part down and keep the rest going.... hope that makes sense.
Both of my zone pumps are on 24/7. I have 2 thermostats controlling each of the furnaces, and the little electrical valves for the 3 floor zones.
"WHY DOES THIS CROSS BACK INTO RETURN?" Yes... that is my poor drawing of a mixing vavle.
I do have some bleeder valves in my system too, can't remember exactly where they are, but I think I have one at each furnace, and one at the floor zones or something like that. Might not be a bad idea to use all bleeder valves if the price aint much different...?
You won't need a "fill valve" for your floor loop, that second pump and a bleeder vavle should do the trick.
Hope this helps.
From one dummy to another....
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Topic: Adding radiant floor heating (Read 5248 times)