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Design Envelope 4382 dualArm Pumps

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  • Summary
  • Applications

    HVAC-system pumping; general purpose pumping; industrial/process pumping (water or glycol based) 
    Armstrong Design Envelope Pumps with integrated controllers are OSHPD pre-approved!

  • Description

    Pipe-mounted 2-pump unit with integrated intelligent controls for space-saving installation, superior energy performance, and full redundancy or parallel-pumping operation.

  • Materials
    • Cast iron or ductile iron casing
    • Cast iron or bronze impeller
    • Sintered silicon carbide mechanical seal
  • Configuration

    On-board Intelligent Variable Speed controls with Sensorless or Parallel Sensorless control. Controls enclosure UL type 12 or UL type 4X (outdoor applications). NEMA premium motors. Inside single-spring mechanical seals

  • Performance range

    Up to 1000 USgpm (63 L/s) flow; up to 140 ft (43 m) head

  • Temperature

    250o F (121o C)

  • Power Range

    0.33 hp to 7.5 hp (0.25 kW to 5.5 kW)

  • Size

    1" to 8” (25 mm to 200 mm)

Lowest installed cost

  • Vertical In-Line design eliminates the need for inertia bases, housekeeping pads, and flex connectors and reduces piping requirement
  • 2-pump casing for reduced footprint
  • Integrated intelligent controls eliminate procurement, installation (incl. wiring), calibration and maintenance of differential pressure sensors
  • 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 pumping installations
  • Optional Parallel Sensorless control (patent pending) with best-efficiency staging of both pumps for additional energy savings
  • Shorter pipe runs for reduced 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 dualArm 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 – combined with perfect component match-up and tuning – make commissioning fast and easy
  • Integrated controls reduce radiofrequency interference and improve  electromagnetic compatibility
  • DualArm design for full redundancy in case of emergency or routine servicing (each pump can be individually isolated from the system with the second pump still operating)
  • ETL Listed - conforms to UL STD 778
  • Certified to CSA STD C22.2 NO.108
  • OSHPD Special Seismic Certification Pre-approval (OSP) No OSP-0422-10
Tridel Ventus

Case study: Living up to LEED

Tridel's Ventus at Metrogate is 85% more energy efficient after retrofit.

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 single-phase power supplement

Variable frequency drives and the use of bypasses - fact sheet

Armstrong Design Envelope - FAQs

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 (single-phase)




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