Installing mechanical for slab radiant heat. When using the Closely Spaced Tees (Hydro Separator) method should the circulators (one in the boiler circuit side of the tees & one in the distribution circuit other side of the tees) be on the supply side or return side? I have seen diagrams indicating both ways. Which would be correct?
A parts supplier has indicated needs to be on return side for maximum flow over primary & secondary heat exchangers in a Takagi wall hung condensing boiler. If on supply side may have too much head loss to achieve proper flow over heat exchangers.
TKS,
Dennis

If on supply side may have too much head loss to achieve proper flow over heat exchangers.
TKS,
Dennis, you match the circulator to the head loss. if there is any doubt, use a 3 speed circulator (taco 0015) and try for a delta temperature differential of 10-15 deg F...

Takagi is making boilers now? At any rate...you follow the manufacturers recommended piping diagrams. They all have them in their I&O manual. Some mod/con manufacturers want the primary circ on the return side to avoid pump cavitation. But that is manufacturer specific, and again, the I&O manual will tell you. Do not attempt to use a water heater as a boiler, if that is what you are doing.



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