Collection: Armstrong Pumps & Circulators

491 products

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Discover a comprehensive selection of Armstrong Fluid Technology pumps, circulators, and OEM replacement parts. Known globally for energy-efficient fluid flow and heat transfer solutions, Armstrong delivers industry-leading reliability for both residential hydronics and heavy-duty commercial HVAC systems. Browse our inventory of wet-rotor circulators, 3-piece in-line pumps, and repair kits below.

High-Efficiency Armstrong Pumps for Every Application

Armstrong Fluid Technology is a leading global manufacturer of heating, ventilation, air-conditioning, and cooling equipment. Whether you are outfitting a commercial building or upgrading a residential hot water system, Armstrong provides energy-saving pump solutions engineered for maximum efficiency and minimal lifecycle costs.

Popular Armstrong Product Lines

  • Astro 2 & E.2 Series Circulators: Zero-maintenance wet-rotor circulators designed for quiet, efficient operation in residential hydronic heating, radiant floor systems, and geothermal loops.
  • S&H Series 3-Piece Circulators: Durable fixed-speed in-line pumps built with a modular, back pull-out design for simplified shaft and bearing assembly maintenance.
  • Design Envelope & Commercial Pumps: High-performance vertical in-line, end suction, and split-case pumps equipped with intelligent variable-speed controls to cut energy costs.
  • Genuine Armstrong Replacement Parts: Authentic seal kits, bearing assemblies, flange hardware, and pump-less-volute repair kits to keep your system running smoothly.

Need help sizing or cross-referencing an Armstrong pump? Contact our technical support team to verify flow rates, head pressure, and model compatibility before you buy.