Butterfly valves

A more durable butterfly valve design that lasts even longer.

Butterfly valves are the workhorse in a hydronic system used to isolate flow with bubble-tight shutoff. At Siemens, we continuously challenge ourselves to improve butterfly valves to exceed hydronic system demands with improved performance, efficiency and value. So we set our sights on designing the best version of the most widely used resilient seated butterfly valve to be more durable to last even longer -- delivering better value. These motorized butterfly valves are ideal for chilled water, hot water and open-loop cooling tower applications.

View this brochure for complete information on our resilient seated Butterfly Valves.  Download now >

Available in 2- to 24-inch sizes (50 - 610 mm) with Cv ranging from 144 to 33,154. Siemens butterfly valves control hot and chilled water with up to 50% glycol over a temperature range of -40° F to 250° F. Used with A-Series industrial actuators and OpenAir™ damper actuators.


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  • 2" to 24" sizes (50 - 610 mm)
  • Full cut / under cut discs
  • 2-Way / 3-Way assemblies
  • ASTM A126 Class A cast iron body
  • 316 Stainless Steel disc (2" - 12")
  • Electronless nickel plated ductile iron disc (14" - 24")
  • 416 Stainless Steel stem
  • Heavy duty acetal stem bearing
  • High purity, peroxide cured, high temperature EPDM seat
  • -40° F to continuous 250° F (-40° C to 121° C) temperature range
  • Nitrile butadine rubber packing
  • Fits ANSI 125 flange
  • Resilient seated molded-in valve provides bubble-tight shutoff up to 175 PSI
  • On/off, floating and modulating control signals
  • Fail-in-place industrial butterfly actuators
  • Fail-safe operation with OpenAir actuators
  • Resilient, high-temperature EPDM seat suitable for continuous 250° F applications 
  • Corrosion resistant disc optimized for open loop cooling tower applications
  • Bubble-tight shut off with zero leakage eliminates wasted energy
  • Provides years of trouble-free maintenance
  • Extended neck provides clearance for flanges and piping insulation 

• Central plant equipment

• Cooling tower bypass

• Isolation

The valve should always be installed with the disc open at 10°


See pages 14 and 15 in technical instructions for complete information


1. Lower the valve into the open pipe work with the disc in the 10° open position. Valves with non-spring actuators are shipped in this position.


2. Once the valve is placed in the pipework, turn the disc to the full-open position. Gradually remove the flange spreaders.


3. Center the valve body to the flanges and tighten the bolts hand-tight. Slowly close the valve clockwise to check for adequate disc clearance.


4. Return the disc to the full-open position and cross tighten all bolts to the proper torque specifications.


NOTE: Do not install with the disc in the fully closed position This will cause seat distortion. When flange bolts are tightened, the rubber will close around the disc edge creating excessive breakaway torque in the initial operation. The valve should always be installed with the disc open at 10°.


Installation is now complete.

Installation warning: Do not lower valve into the pipe with pipe work spread insufficiently; do not use flange gaskets, incorrect pipe alignment can cause interference.

Replace Emerson/Keystone EPI2 actuators with Siemens butterfly valve retrofit kits

Siemens Retrofit Kits are a quick, easy, and cost-effective solution to replacing failed Emerson/Keystone EPI2 actuators. The kits are available to retrofit 2-way valves, sizes 2-12" and enable field assembly of Siemens actuators onto Emerson valves.


View page five in the Retrofit Kit Brochure for the 2-way valve selection guide

A better resilient seated butterfly valve

Highly corrosion resistant

Siemens uses robust disc materials that help ensure valves perform in the harshest conditions.

  • Valve sizes 2”-12” use high quality 316 stainless steel
  • Valve sizes 14”-24” use electroless nickel plated ductile iron     

Greater durability

Our high purity, peroxide-cured high temperature EPDM seat is built to last in continuous 250°F applications. Additional resilient seated advantages:

  • Better shape and memory retention over the service life of the valve
  • Molded tongue-and-groove design lowers torque, while also providing bubble-tight shutoff.

Higher reliability

Every Siemens valve and actuator are tested from the factory line to assure longer performance and bubble-tight shutoff for 0% leakage. Lifecycle testing performed at continuous 250° Fahrenheit and meets ANSI 125 standards.

IMage of Siemens valve connected to piping

Built to last at 250°F continuous applications

Siemens resilient seated butterfly valve series is designed with the best materials to withstand continuous high temperature operation and built and tested to Siemens standards.

Free factory assembly and valve tagging

Valves and valve actuators are assembled and tagged for direct delivery to any jobsite, free of charge. All you do is specify each valve’s location when placing your initial order and we will tag them before shipping to save you installation time and expense.


For questions call 800-516-9964 or email bgcustomersupport.us.sbt@siemens.com    

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