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Hydro Coil

Bill_31 Member Posts: 6
Want to use a Bosch Tankless, water heater to support a Unico hot water coil (heating only)


  • njtommy
    njtommy Member Posts: 1,105
    ok well it's doable should be no problems but we need more information.
    What water temp do you need to supply enough btus to your coil?
  • hot_rod
    hot_rod Member Posts: 21,793

    Tankless heaters are designed for low flow, high delta T operation. The small diameter HX tubes typically require a high head circ to get any performance, and may not ramp to full burner output with a pumped flow.

    Use a boiler designed for the application and enjoy all the added benefits, ODR, ramp and delay functions, warranty, and piece of mind.

    You have chosen a good brand, but the wrong product, look into their boiler options.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream