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Cast iron baseboard

bob eck
bob eck Member Posts: 930
How many feet of cast iron baseboard can you run on one loop. 3/4” copper M will be run to the cast iron baseboard or should 1” be run to it.
Anyone know what GPM that cast iron baseboard can flow at.
Can 4 GPM be run through the CI baseboard.


    EBEBRATT-Ed Member Posts: 15,844
    You need to find the max flow rate from the baseboard mfg. 4 gpm is standard. 4 gpm with a 20 degree TD will give you 40,000 btu. Take btu rating/foot at the average water temp you are using.

    40,000/btu rating/ft = footage to install
  • Ironman
    Ironman Member Posts: 7,399
    In theory, not more than about 65'. A 3/4" line can carry about 4 gpm or 40k btu at a 20* delta T.

    The Baseray manual that I have gives the same two flow rates as fine tube: 1gpm and 4 gpm. So 4 gpm should be possible, but the radiator's output is only slightly higher (450 btus per ft. @170* average SWT).
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.