Circulator Pump Wilo Star S21 RFC
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Circulator Pump Wilo Star S21 RFC

Product Code: TJ-WILS21RFC


The Wilo Star S21 RFC is a 3-speed cast iron circulator pump with built-in flow check. 3 speeds (Low/Med/High) of the Wilo Star S21 RFC make this model very versatile and allow to use it in a large variety of heating applications inlcuding radiant, hydronic, radiators, fan coils, etc. A built-in flow check eliminates the need to buy and install a separate in-line check valve. This circulator is designed for closed loop systems with medium to high flow rates and pressure drops.

Wilo Star S21 RFC circulators are also available in stainless pump housings which are suitable for hot water recirculation as well as other system applications.

Number 4171560

  • Heating residential and small commercial applications
  • Reliable wet rotor technology
  • Water/Glycol concentrations up to 50%
  • Quick connect wiring
  • Ultra quiet
  • RFC Patented Rotating Flange:
  • Includes (2) Gaskets (O-rings) and check valve .
  • ETL/CSA listed.


  • Closed loop radiant heating & snow melting systems.
  • Baseboard, Radiator, Fan coil heating and other hydronic heating and cooling applications


 Model Number

S21 RFC 

 Pump Housing Cast Iron 
 Number of speed  3 
 RPM 1300-2700 tr/min 
 Type motor 2 Poles 
 Power consumption Speed (1) 60 W 
 Power consumption Speed (2) 85 W 
 Power consumption Speed (3) 110 W 
 Amperage Speed (1) 0.55 A 
 Amperage Speed (2) 0.75 A 
 Amperage Speed (3) 0.95 A 
 Voltage  115v 
 Hertz  60 Hz 
 Phase  1 
 Connection Port Flange 2 holes rotary RFC
 Power HP 1/25 HP 
 Max. Flow 19 GPM 
 Max. Head/Feet 21 Ft 
 Working Temperature (liquid) 14°F (-10°C) ~ 230°F (110°C ) 
 Max. Pressure 140 PSI 
 Certification CSA, ETL 


Performance Curve Wilo Star S21 RFC 

Brochure Wilo Star S21 RFCProduct Brochure

Specification Wilo Star S21 RFCProduct Specification


CAD $168.50