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    Taco pump problem (5 Posts)

  • gtsdlss gtsdlss @ 10:07 AM
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    Taco pump problem

    My pump was making noises, so I replaced the cartridge a few months ago. The pipes are now ringing, especially on the return side of the boiler. The pump was the older 0010-F1. I ordered the "correct" replacement cartridge. Prior to installation, I noted that the impellers were quite different. The old impeller was closed (similar to a higher head model- looks similar to the impeller of Tac0012-011RP ) and the new one was relatively flat and open. I called Taco, and they assured me it was the correct one. I'm now thinking that sometime in the past, and possibly at the original install, a different cartridge was plugged in from one of the higher series pumps.

    Here's what I have:
    112,500 BTU McNeil
    2 story home ~1350 SF per floor
    220 equivalent feet of piping, 3/4" system
    Burner in the basement
    2 loops, one 1st floor, one 2nd floor with auto valves
    0010-F1 pump, 1/15 hp, 3250 RPM

    Questions:
    Does anyone have any direct experience with the interchangeability?
    What size replacement pump would be appropriate?
    I did some calculations based on this link, http://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf and it looks like I need a Model 0012 which would give me a head versus flow crossing point of ~6 to 7 gpm (or am I totally wrong?).  This would tend to support the cartridge swap theory.
    Or would the Grundfos UPS15-58FC be a good choice?
  • Chris Chris @ 11:26 AM
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    Longest Loop

    Don't care about total piping run. Just the longest which I would believe would be the second floor. What's the total run from the circ through that zone back through the boiler to to the inlet of the pump?

    I'll use 150 feet and it's piped copper not pex just to explain.

    150 x 1.50 x .04 = 9' Head
    Flow based on the boiler and a 20 degree delta t = 11gpm
    Your pump should be able to deliver roughly 11gpm @ 9' head.....A 0010 is breathing on the edge with this basic rule of thumb formula. Curves attached
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
    This post was edited by an admin on January 29, 2011 11:29 AM.
  • gtsdlss gtsdlss @ 12:14 PM
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    Calculation

    Is the calculation missing some decimals, or a factor?
    I have ~ 225 equivalent feet of 3/4" copper piping
  • Chris Chris @ 1:27 PM
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    The Longest Run

    If the longest run (zone) is 225 feet then:

    225x1.5x.04 = 13.5ft head

    The 1.5 is the rule of thumb formula for added friction loss in the copper, fittings, valves, etc. The .04 represents water moving at 4ft per second.  So you need a pump that can move 11gpm at 13.5ft of head..Which will not be that 0010... 
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • CC.Rob CC.Rob @ 9:00 PM
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    TEL

    If you followed the Selecting Circulators approach, and came up with 225 feet of equivalent length for your longest zone, then....

    For TEL = 225 ft

    gpm    head(ft)   
    3.5    5.55
    4    7.01
    4.5    8.61
    5    10.35
    6    14.24

    So you can flow 4 gpm at 7 ft of head. Taco 007 would be fine for typical residential application (and with that you might be up around 5gpm; perhaps a bit much). Or go with the Grundfos 15-58 if you want to play with speeds. Or go fancy with an ECO or Alpha if you want lower electric use and some pump 'smarts'.
    This post was edited by an admin on January 29, 2011 9:03 PM.
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