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CI Radiator Re-pipe - Primary/Secondary vs Boiler Bypass
I'm in the middle of a radiator re-pipe of a converted gravity system. Cut out the supply and returns and replaced with home runs of Pex-Al-Pex to a manifold. I had originally planned to keep all the near boiler piping the same as it was since it had been working well to this point. I didn't see any reason to change anything. Had a Taco 007 on the return side to run the whole system (1 zone, 8 rads). However, by the looks of the flue, there was some pretty good condensation going on. I need to remedy that moving forward. Looking pros and cons for Primary/Secondary vs Boiler Bypass arrangements. If I go with Primary/Secondary do I need to add additional controls to run the additional pump?