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Design Envelope 4322 Tango Pumps

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Design Envelope Tango Isometric
Design Envelope Tango Isometric
Design Envelope Tango Isometric
Design Envelope Tango Isometric
Design Envelope Tango Isometric
Design Envelope Tango Isometric
Design Envelope Tango Isometric
Design Envelope Tango Front

  • Summary
  • Applications

    HVAC-system pumping and control; general purpose pumping; industrial/process pumping and control (water or glycol based) 

  • Description

    Pipe-mounted 2-pump unit with integrated intelligent controls for space-saving installation, superior energy performance, and parallel-pumping or full redundancy operation. Saves up to 75% in energy over comparable traditional constant speed or variable frequency operated pump installations. Remote services through internet to enhance reliability and sustain optimal performance over life of pumps.

  • Materials
    • Ductile iron e-coated casing
    • Stainless steel impeller
    • Sintered silicon carbide mechanical seal
  • Configuration

    On-board Intelligent Variable Speed controls with Sensorless control. Split-coupling design and outside balanced or inside single spring mechanical seal. Controls enclosure UL type 12 or UL type 4X for outdoor applications. 1-10hp range standard with DEPM motors that reduce losses by more than 20% over NEMA Premium efficiency.  Network capable for remote performance management services.

  • Performance range

    Up to 900 USgpm (56 L/s) in parallel flow and 160 ft (48 m) head (composite curves available)

  • Temperature

    300˚F (150˚C)

  • Power Range

    0.33 hp to 10 hp (0.25 kW to 7.5 kW)

  • Size

    1" to 3" (25 mm to 80 mm)

Lowest installed cost

  • Vertical In-line design eliminates the need for inertia bases, housekeeping pads, and flex connectors and reduces piping requirements
  • 2-pump casing for reduced footprint
  • Integrated intelligent controls eliminate separate mounting of variable frequency drive (VFD) as well as procurement, installation (incl. wiring), calibration and upkeep of differential pressure sensor
  • Superior energy performance qualifies for significant cost recovery under utility and government rebate programs
  • Design Envelope selections frequently recommend a smaller motor and/or pump which reduces installed cost.

Pump Models Designed and Engineered for Outdoor Operation

Controls enclosure rated for UL type 4x. Equipped with overhead weather shield to prevent icing in cold weather or overheating in direct sunlight.

Lowest operating cost

  • Integrated intelligent controls – combined with perfect component match-up and tuning – for up to 75% in energy savings over traditional constant speed and variable frequency operated pump installations
  • Standard with Parallel Sensorless control (patent pending) to provide best-efficiency staging of both pumps for additional energy savings
  • Shorter pipe runs reduce system friction
Design Envelope

Lowest installed cost. Lowest operating cost.


Lowest environmental cost

  • 75% decrease in energy consumption reduces operational greenhouse gas emissions at equal ratio
  • Elimination of inertia bases, housekeeping pads, flex connectors and superfluous piping avoids all procurement related environmental impacts (material, energy, carbon)
  • Equipment downsizing mitigates environmental impacts associated with procuring unnecessarily large equipment
  • Integrated design packs and ships more economically for less packaging waste compared to loose component shipping and assembly



Lowest project and operating risk

  • Integrated intelligent controls for fast and easy commissioning as well as reduced radio frequency interference/ improved electromagnetic compatibility
  • Optional performance management for early warnings, online trending and analysis, and reports and summaries
  • Optional sediment filters or separators for extended seal life in contaminated systems
  • Single-source responsibility for optimum design and field support
  • Independent operation through embedded Sensorless control or in conjunction with a building automation system (BAS)
  • ETL Listed - conforms to UL STD 778
  • Certified to CSA STD C22.2 NO.108
Florida power and light

Case study: Supplying energy and leadership

Florida Power & Light has reduced energy costs 68% by upgrading their HVAC system with Design Envelope pumps.

Learn more


U.S.A. Utility Energy Rebate Info.

360 Service and Support

Design Envelope IVS Pumps with Cloud Based Active Performance Management – solution outline

Design Envelope Tango - solution outline

Design Envelope pumps mitigate motor bearing damage - white paper

Saving Energy by Piping Configuration - white paper

Evolution of Pumping Technology and Superior Performance Base mounted - white paper

Fused Disconnects for use with Design Envelope Pumps - white paper

Design Envelope pump vs. a variable speed drive on the wall - white paper

E-Coating - white paper

Working Clearances of Design Envelope Pump Controls - WhitePaper

Submittals (DEPM)


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