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Baseboard pump question

acl10 Member Posts: 349
The basement has baseboard that runs through the main gas boiler which also gives steam. I just put in a new pump that has three speeds. What is the best and most efficient speed to run the pump for the baseboard at?


  • furnacefigher15
    furnacefigher15 Member Posts: 514
    Multi speed pump.

    It depends, on how much flow you need.

    What was the old pump?
  • furnacefigher15
    furnacefigher15 Member Posts: 514
    new pump

    And what is the new pump?
  • acl10
    acl10 Member Posts: 349
    Pump Armstrong

    Old pump was armstrong Astro30 closed cast iron. The new is the updated edition of the Armstrog 30 that has 3 speeds.
  • furnacefigher15
    furnacefigher15 Member Posts: 514
    new pump

    Based on the pump curve, the 3rd speed (high) is the same as the original pump curve. So that is what I would use.

    This one applies to the astro 30

    this one is the 3 speed astro 30
  • icesailor
    icesailor Member Posts: 7,265
    Wet Rotar pumps:

    I thought I read here that you shouldn't use wet rotar pumps on a steam condensate boiler water. The crud in the water wrecks the pump motors.

    That a 3 piece pump is the circulator of choice. Like a B&G Series 100 or a Taco 110.
  • furnacefigher15
    furnacefigher15 Member Posts: 514
    that's probably true

    But, in my experience, even in standard hot water systems, the three piece pumps are not lasting like they use to (bearings are going bad left and right). So, 6 of one, 1/2 dozen of another.
  • Big Ed_4
    Big Ed_4 Member Posts: 1,780
    edited December 2011
    Seal Leaks

    Correct , the seals on the three piece can gather solids and leak ... But where do the solids come from ? Steam leaks , the water boils out leaving solids behind ....

    Add more water and add more solids .... Fix the leaks , a tight system would use less then a gallon a year ... Fixing leaks saves a lot of fuel
    I have enough experience to know , that I dont know it all
  • furnacefigher15
    furnacefigher15 Member Posts: 514
    seal leaks

    I find seal leaks across the board, not just on the steam setups.

    Just plain old hot water.

    Replace that 30 year old work horse, b/c it finally sprung a leak, and what do you know, the very next season that brand new pump sprung a leak.

    There's more to it than TDS in the water, it's a lack of quality in the new pump seals, and or oil wicks in the bearings.
  • SWEI
    SWEI Member Posts: 7,356
    3-piece pumps

    How many of them get the regular lubrication they need?  Only takes a minute, but most homeowners (and an unfortunate percentage of service techs) don't seem to know.

    Armstrong S25 is a direct match for the Series 100.
This discussion has been closed.