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Pipe Size from Feeder Pump to Multiple Boilers??

JUGHNE Member Posts: 8,368
edited May 30 in THE MAIN WALL
I will have 2 boilers with solenoid controls fed by a single boiler feeder pump.
(ShipCo 60-DMS-MU1; 1/3HP; 6 GPM @ 10 PSI; 34 gallon tank)

I was thinking of using 1/2" black pipe from the pump to each boiler.
(M&M 150 feeder/LWCO controls on each)

I have another site with the same pump feeding 2 slightly larger boilers that sends water thru 3/4" blk pipe too quickly and knocks the steam down. It has a nearly full port 3/4" bypass from pump discharge directly back into the tank. There are 2 throttling ball valves on each boiler plus the drop thru 3/4" electric valves. It still fill too quickly.

I thought 3/4 at the pump reduced to 1/2" to each boiler might knock the flow down better. Boilers are PB-05L with 12.4 gallons of water and PB-04, 10.8 gallons.

If 3/4" is highly recommended then how about 3/4" hard type L copper? (my stock cost less than 3/4" blk pipe does today).........also have old stock of 1/2" black pipe.

Trying to empty shop of old stock.....this is probably my last major piping job.


  • Jamie Hall
    Jamie Hall Member Posts: 15,950
    Unless the runs are very long, 1/2 vs. 3/4 isn't going to make that much difference...

    How about using a globe valve on each run? They can throttle more effectively than a ball valve (I know -- pain in the neck to maintain,, but.)

    Or just get a less enthusiastic pump?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    JUGHNE Member Posts: 8,368
    The runs are pretty short, 4-6'.

    In addition to isolation ball valves, I was going to try iron gas cocks, sometimes referred to as "I bibs", IIRC.
    They have the slotted tapered plug, that rotates only 1/4 turn.
    Heavy iron seems like it should not wear down like ball valves.

    This is the smallest pump available, least GPM.
    Unique pump tank is only 9" tall, 30 X 30 square. Needed as inlet is 6 1/2" AFF, existing true "dry" pipe is 9" AFF. 2 pipe system. F&T on EOM....2" return.

    Thanks for your input Jamie.

    I am sure all of us are thankful and remembering the reason for long week end.
    EBEBRATT-Ed Member Posts: 9,104
    I would use the 3/4 copper. If you put in 1/2" and it's too small your stuck. 3/4" with a valve in it to throttle the flow would be better IMHO
  • dopey27177
    dopey27177 Member Posts: 540
    Dole makes in line flow control valves 1/2 & 3/4".
    These are inline orificed fittings fixed at a specific flow rate.
    Can be had from 1/2 gpm and up/

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