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Which Boiler do I need ?

I have a large system in concrete and under subfloor. Needing boiler and mechanical panel. I also need to generate DHW. Looking at the NTI boilers to supply my system.
199,000 BTU, 5 zones, propane. The FTVN and TRX look to be my choices but not sure which one. also is it best to have a DHW storage tank or boiler heat exchanger.


  • hot_rod
    hot_rod Member Posts: 22,244
    How big is the slab, select the correct size boiler based on the load you are connecting to

    DHW from either an indirect tank or a combi boiler.
    It depends a bit on your hot water usage. Combis give you endless hot water at low flow rates, 2-4 gpm

    A tank could supply any gpm, until it runs cool.

    So either a tank sized for the dump load. Or work within the combis output.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Mad Dog_2