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Indirect Tanks and proper Pumping

Quick easy pumping question.
I have a Utica H20 40 gal indirect water heater. It's currently being fed by a Taco 007 ECM pump from a Utica Trifire Boiler 4075. This circulator is dedicated to the DHW tank.
There are 2 other zones but they have their own circulator and the DHW has priority.
The documentation I can find on the tank indicates the ideal flow would be 14 gpm at 5.7 ft head.
Those flow requirements are a bit over what that pump is capable of. It's probably flowing around 12 gpm or maybe around 11 for that head.
Should the pump be ok even though it's a bit under powered or should I look at something more powerful even though at those performance specs it gets pretty pricey?
Or possibly parallel pipe 2 small cheaper 005 size pumps to split the gpm requirements?


  • Zman
    Zman Member Posts: 6,975
    The 007 will work just fine. In order to get the max capacity out of the indirect, the boiler would need to about 50% larger. Moving the water a little faster will have little or no impact on the performance of the system.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • flat_twin
    flat_twin Member Posts: 290
    More important to pump within the specs of the heat exchanger.