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Star S 21 F, 3-Speed Cast Iron Star Series Circulator, 1/12 HP
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$153.24 each
In Stock
Get 42 Thu, Jul 2
Order by today, receive Thursday
MANUALS (4)
This item replaces: 4105031
Free Shipping This item ships free
Easy Returns No restocking fee for 90 days
Product Highlights
–
115V
1/12 HP
Flanged x Flanged Connection
19 MAX GPM
140 MAX PSI
Cast Iron
Description
–
Wet rotor circulation pump, with flanged connection. (Flange perpendicular to shaft). Pre-selectable speeds to adjust the capacity on "S" versions. Cast iron body for hot-water heating systems of all kinds, industrial circulation systems, cold-water systems and air-conditioning systems.
Features:
Materials:
Features:
- Suitable for any installation position with horizontal shaft; terminal box in 3-6-9-12 o'clock position
- Three pre-selectable speed stages for load adjustment ("S" type only)
- Impedance protected motor, motor protection not required
- Cable entry both sides of terminal box
- Quick connection spring clips for simple electrical connection
- Steel Terminal Box
- Fits all Competitor's Models
- Powerful Starting Torque
- Ultra Quiet
- Reliable Wet Rotor Technology
- Optional Check Flange Set
- Automatically Vented
Materials:
- Pump housing: Grey cast iron (EN-GJL200)
- Impeller: Engineered Composite (PP - 40% GF)
- Shaft: Stainless steel (Cr)
- Bearing: Metal-impregnated carbon
Specs
–
| Application: | Heating |
|---|---|
| Material: | Cast Iron |
| Horse Power: | 1/12 |
| Voltage: | 115V |
| Phase: | 1 |
| Hertz: | 60 |
| Temperature Range (F): | 14°F - 230°F |
| Max Pressure (PSI): | 140 |
| Max Flow (GPM): | 19 |
| Max Head (Ft): | 21 |
| Connection Type: | Flanged x Flanged |
| Connection Size: | 1" 1-1/4" 1-1/2" 3/4" |
| Max. Amps: | 0.66 |
| Max. RPM: | 2700 |
| Type: | 3-Speed Pump |
Questions?
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Product Reviews
4.5 out of 24 reviews
92% would recommend this product
5 star
83%
4 star
0%
3 star
8%
2 star
0%
1 star
8%
Customer Images
Most Liked Positive Review
Quiet and powerful pump
My customer is stuck, for now, with 3/4" supply and return lines for an indirect water heater. This pump, when set on "High", puts out just enough to avoid short cycling of customers 140,000 BTU boiler. It is very quiet and puts out way more than the Grundfos Alpha 15-55F that was installed when I arrived. The Wilo can be wired from either side of the electric box, and it has quick connect wire connections inside the box.
VS
Most Liked Negative Review
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Only if it has to go back into an existing pump body
These pumps are installed in solar thermal pump stations. I've had a lot of pump failures in the smaller Wilo pumps. We installed this pump 13 months ago and it failed. We replaced it and that pump failed after 1.5 months. We aren't getting much support from Wilo USA or the local Denver sales rep. I've used the larger Wilo pumps that are still going 15 years later.
Showing 1-10 of 24 reviews
I would buy this pump again
Installed on a single zone hydronic system
Upstate HVAC
New York
6 months ago
Verified Buyer
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I would buy this product again.
Good circulator for radiant floor heating. Easy to install.
Duke
Virginia
1 years ago
Verified Buyer
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Always keep 2 as spares
The time to buy a spare tire is not when your flat on side of hwy. Winter is near. Get a spare pump I r two before everyone else is also ordering the same. These little pumps are awesome! Beautiful little workhorses! And this store is fast to ship your order! God bless America!
doubletappinhillbilly
America
2 years ago
Verified Buyer
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I'll keep buying them
We use these pumps for heating systems. They work excellent, very silent. Sometimes I can't say if they are working or not
Ed
Saltillo MX
2 years ago
Verified Buyer
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Product was what I needed at a great price.
Product worked like it should.
Sam
Kentucky
2 years ago
Verified Buyer
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Short Life
Installed this pump in January of 2023 and now, in January 2024, pump over heats and boiler won't run. Coldest time of the year and we have no heat.
Paige
Pennsylvania
2 years ago
Verified Buyer
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good service
good service, fast shipping, great price!!!
mabo513
owego ny
3 years ago
Verified Buyer
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Definitely buy this product again
Exact fit of old pump. Easy to replace.
Bones
Sparta TN
3 years ago
Verified Buyer
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The customer service is excellent!
I bought parts from Supply House serveral times and everything is great!
John
Algonquin, IL
3 years ago
Verified Buyer
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yes
wood boiler
Stone
Giles County TN.
3 years ago
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Product Q&A
3 Questions3 Questions
Q: Is it suitable for a potable water system?
Asked by Tony 9 years ago
Add your answer
Verified Reply- SupplyHouse StaffThis pump is made of cast iron which would rust out in an open loop potable water application. A pump made of stainless steel would be suggested to use in such an application.
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Q: What is the difference between S21F and s21FX
Asked by 14 years ago
Add your answer
Verified Reply- PexSupply StaffThe S21FX is a rotated-flange version of the same circulator. Its flange connections are rotated 90 degrees.
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Q: WHATS THE R PM & WILL THIS UNIT INTER CHANGE WITH A TACO 00700 SAME DIA SAME FLANGES?????
Asked by buster 15 years ago
Add your answer
Verified Reply- PexSupply StaffIt is 3250 RPM. You can use the Taco flanges.
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