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Having trouble picking a replacement zone circulator

mackworth
mackworth Member Posts: 2
in Radiant Heating
I have a navian 240e that was installed a few years ago. I don't think they installed the right circulators. One of them is making horrible noises so I wanted to take this time to replace it with a correct one but I can't quite figure out what I need. I currently have a Grundfos UPS15-58FRC.

This is my second floor zone. I ran a manual J using cool calc and got about a 14,000 BTU heat load and I usually run my water temp at ~140 degrees.
It is currently piped with 3/4 copper and I measured 178 feet of pipe and 16 90s. It's a continuous loop.

I followed this guide here: http://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf

First, for GPM, assuming a 20 degree temp difference -> 14,000/(500*20) = 1.4 GPM

Then for calculating head, I followed HL =k*c*L*(f1.75) where:
HL = the head of the piping system (feet of head)
k = a number based on tubing type/size (found in Table 3)
c = correction factor for fluid type and temperature (found in Table 4)
L = total equivalent length of piping circuit (feet) (from Step 3)
f1.75 = flow rate through piping (gpm) raised to 1.75 power (selected values found in Table 5)

So that means 0.00295 * 1.000 * 210 * 2 = 1.23 feet

So given the 1.23 feet of head and the 1.4 GPM, I think that means I would want the Taco 006e running on min. If I dropped to a 10 degree temp diff I could also set it Low. Did I do this right? https://www.tacocomfort.com/documents/FileLibrary/006e3_iSheet_102-533.pdf

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