The below-listed sources serve as references and proof for the different statements used in the Digital NEXT campaign promoting the launch of UPSe and ALPHA.


By using a constant flow that corresponds to the design flow (compared to just choosing constant curve setting III) 25% of electricity is saved. The constant flow is set via the Grundfos GO app through the guided setup. The guided setup will also help to calculate the right flow.

The power consumption of the control modes is based on a simulation study that introduced several system configurations. ​

The power consumption for each control mode is obtained by various system configurations:​

  • Houses: 3​
  • Weather profiles: 5​
  • Supply flow resistance: 2​
  • Thermostat hysteresis settings: 2​
  • Design pressures: 3​ (corresponding to constant curve I, II, and III)
  • SimulatedoOperating time: 365 days​

Total number of simulations per control mode: 180​


Annual savings is based on replacing a non-compliant circulator of the same horsepower (minimal compliant circulator has a CEI of 1.00).

Example: The $46 saving is based on proportional pressure I for UPSe or ALPHA vs. constant curve III for a performance-wise equivalent non-ECM pump.

CEI: Circulator Energy Index

  • Legislation expected to take effect 2027
  • Calculation is based on 4 load points with different weighting (25, 50, 75 and 100% of BEP)
  • Rating based on most efficient / least consumptive control mode
  • Below 1.00 CEI to be legal to sell
  • Lower CEI means a more efficient circulator

HI Energy Rating Program

  • Based on CEI
  • Higher ER means a more efficient circulator
  • Program went live summer of 2021
  • Expecting rebate schemes to be written around ER moving forward


During a period of 5 months, multiple pumps were tested in standstill in tap water. After 2 months of standstill, 25% of the pumps were started, the following month an additional 25% were started, and so on until the fifth month when all pumps had been started. During the five-month period, 8 pumps were blocked at startup due to lime. Out of the 8 pumps, the robust start-up functionality was able to unblock 5pumps within 1 hour of power ON, corresponding to 60% of blocked pumps. The period during which the pumps were off depended on the climate zone and application. It is assumed that pumps are rarely turned off for more than 5 months in a real-world application, but that some are only switched off during a 2 month period.

Internal reference number: Test & Verification report Case No: 170619_202644_46884


A total of 706 product numbers have been added to the replacement list in the Grundfos GO app.  This includes Grundfos, Taco, Armstrong, and B&G. Some of these are medium and large circulators which are eliminated for this calculation (everything over 22 feet of head and over 20 gpm). That leaves 364 product numbers remaining. Out of these, the ALPHA (F, FR, SF or SU) or UPSe replaces 329 of them; equal to 90%. 

Some pumps are not compatible:

  • Taco has a handful of VT products that are either delta T or external signal controlled; 006-VRF4; 007-VRF5, and others.
  • Grundfos ALPHA pumps are sold to some OEMs with union housings. 


All quotes used in the Digital NEXT films are from interviews with American installers conducted in September and October 2021 by Lindberg International.