Pump Curve Help Please

Bostopa

Hi all I'm looking at two Grundfos pumps both 15-58FRC & 15-58UPS.

Trying to figure out do both have the same curves or are the different. I dont understand the curves from the two.

15-58UPS below

Jamie Hall

Yes and no. The top graph shows the actual inherent performance curves for the pump operating at three different power levels. That graph shows what the pump — without other controls — will accomplish. The bottom diagram shows the effect of three different electronic control strategies which the "e" version oof the pump can be programmed to do:

hot_rod

The first set of curves shows the 15-58 with and without the internal check valve, so a small difference.

The "c" in the model number is for internal check valve versions. FR is for flange rotated versions.

Bostopa

Can the second curve/pump depending on how its programmed/set mirror the first pumps curve or are the completely different….just trying to undertstand is it worth buying the 15-58 UPS

Jamie Hall

https://forum.heatinghelp.com/discussion/comment/1887433#Comment_1887433

The pump itself is exactly the same. The difference is in the controls.

Bostopa

Its for monoflo system not sure if going from FRC to UPS gets me anything

GGross

The pump is identical it is just showing with and without the internal check valve.

the base model is UPS15-58 then you may find FR FRC FC the "R" is for rotated flange, the "C" means it comes with a check valve. Either way the base model will start with UPS15-58

Be aware when you buy one the boxes now have all of those model number variants on them, the specific variant can always be identified with the long form part number if needed for example the US version of the UPS15-58FC has a long form part number 59896341 the rotated flange variant ends in 3 instead of 1

hot_rod

MonoFlo systems can have a high pressure drop, what circulator is currently on it?

Ideally you want to run in the middle 1/3 of the curve. So that 15-58 is comfortable in the 5-11 gpm range. Head depends on which speed. So about 8 gpm at 12' on speed 3.

Is the system zoned? TRVs on radiators as an example? If so an ECM delta P circ, the Alpha or Magna series, is a good match up.