Alpha2 15-55F Variable Speed Circulator Pump w/ IFC, 1/16 HP, 115V

Discontinued Alpha2 15-55F Variable Speed Circulator Pump w/ IFC, 1/16 HP, 115V

The 99163903 from Grundfos is a Alpha2 15-55F Variable Speed Circulator Pump w/ IFC, 1/16HP, 115V. The Alpha2 15-55F model is made of cast iron and has an AutoADAPT feature. This pump is designed for a variety of hydronic and radiant heating applications. Direct replacement for older Alpha model 59896877.

Grundfos: UP15-10F, UP15-42F, UPS15-58FC;
Taco: 005-F2-2, 007-F5, 008-F6, 00R-MSF, 0015-MSF3
B&G: NRF-22, NRF-9F/LW
Armstrong: Astro 230CI, Astro 250CI, Astro 20, Astro 25, Astro 30
WILO: Star S 16F, Star S 21F, Star S 21RFC, Stratos ECO 16 RFC.


  • New and improved version of Grundfos bestselling Alpha circulator;
  • AutoADAPT feature allows the circulator to adapt to changes in the hydronic system to maximize energy savings;
  • Push button allows to select between AutoADAPT, constant speed (3 settings - Hi/Med/Low) or constant pressure (3 settings) modes;
  • Large LED display;
  • Built-in check valve;
  • Insulation jacket and (2) gaskets (O-rings) included;
  • Permanent magnet motor technology with robust startup enables pump to restart indefinitely when rotor is blocked;
  • Cast iron body for closed-loop heating applications;
  • Standard flange accepts Grundfos GF15/26 and other brand flanges;
  • Hardwire model;
  • Made in the USA.

Technical Specifications:

  • Voltage: 115V;
  • Amperage: 0.65A;
  • Hertz: 60;
  • Phase: 1;
  • Watts: 5 - 45W (depending on mode selected);
  • Wiring: Hardwired;
  • Temperature Range: 36°F - 230°F;
  • Max Pressure: 150 psi;
  • Flow range: 0 - 21 GPM;
  • Head Range: 0 - 19 ft of head;
  • Material: Cast Iron;
  • Application: Heating only.


  • 1 year from the date of installation 


Product Specs
Amperage: 0.65A
Application Heating only.
Flow Range: 0 - 21 GPM
Head Range: 0 - 19 ft of head
Hertz: 60
Material1 Cast Iron
Max Pressure: 150 psi
Phase: 1
Temperature Range: 36°F - 230°F
Voltage 115V
Watts: 5 - 45W (depending on mode selected)
Wiring: Hardwired

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  • Views: 7410
  • Alpha2 15-55F Variable Speed Circulator Pump w/ IFC, 1/16 HP, 115V QR Code
  • Model: 99163903
  • MPN: 99163903
  • Availability: Discontinued
  • $ 230.95


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Tags: Circulator Pumps, Heating, Heating Supplies, Condensing Boilers, Heating and Cooling