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water volume in cast iron rads.

oreo123 Member Posts: 48
Setting up new boiler and will add corrosion and scale inhibitor. We need to calculate the volume in three cast rads from around 1950.
Does anyone know where I can find the formula?
52 wide * 19 high * 8 deep 6 tubes, 30 rows (one "ballpark" formula showed 10-12 gallons)
52 * 19 *8 6 tubes, 32 rows
22 * 19 * 4 4 tubes, 12 rows


  • kensheets2
    kensheets2 Member Posts: 36
    here is some data I've collected that should get u in the right direction.

  • kensheets2
    kensheets2 Member Posts: 36
    Sorry, these are to determine btu, u needed volume.  I got nothing :)
  • Jamie Hall
    Jamie Hall Member Posts: 23,415
    I remember a trick passed down to me from a man who worked with Thomas Edison...

    Put a hose and a fitting on one end. Cap the other. Raise one hose above the radiator. Open the bleeder. Pour water into the hose until the bleeder squirts. Now lower the hose and let the radiator drain into a bucket with volume markings on it. Done.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    JUGHNE Member Posts: 11,074
    Or if you have an accurate utility water meter in your house, (you could check it with 1 or 2 five gallon bucket fills in the tub), then with no other water passing, fill your system completely up.
    Bleed all the air out of every thing. Read the meter.
    Drain the system down, this is good for leak check and flushing the old system also.

    If no meter, you could fill as above and measure with the 5 gallon buckets as you drain.....nice to have a floor drain in any case.
  • oreo123
    oreo123 Member Posts: 48
    the rads are all connected in a second floor apt (of a three floor apt building). Each floor has its own boiler.