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proper size and operating cost

Do a up-to date heat loss. Look at worst case winter moment for your area. Then decide. Remember that you can down size, (turn down the T/S or refire the boiler), but after installation, cannot install more heat if the weather goes south! Its like layering clothing, to much and you can take it off, but when needed hard to find.


  • john_230
    john_230 Member Posts: 11
    boiler selection / size

    I am installing a cast iron boiler in a residential house. Current boiler is a steel boiler with 114 btu

    House is 3,300 sq feet and has 170 linear feet of baseboard + a 40 gal indirect water heater.

    Above grade heat loss estimated at 100,000 btu +/-, before water.

    The 3 section which hs a factory setting of 89,000 net btu, can be up fired to 112,000 net btu, max (high fire nozell).

    The 4 section which fires at 130,000 net factory setting, can be down fired to 101 btu (low fire nozzel).

    Which will have lower operating cost. Is the 4 section considered oversized.

    What is the most cost effective / best way to configure; a) the 3 section with a high fire nozel and system slightly under, but near capactiy - or the larger 4 section system ( can fire at either 101 btu, or 130 btu).

    Which system would you go with.

    thanks in advance,

  • rich pickering
    rich pickering Member Posts: 277
    I'd take...

    the 4 section over the 3 section at the same firing rate, especially if firing the 3 section at its max rate.
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