Armstrong 4280 S-11-1/2 Repair Kit

Kit to replace seal in Armstrong Model 4280 New Style circulator.

New style circulator can be determined by the discharge line being in the center of the volute. The old style design has the discharge line offset to on side.

Includes 11-1/2" casing gasket

Shaft shaft sleeve

Mechanical seal

Correct seal replacement kit for:

4280 4x3x11.5,  with 1150 RPM motor 2 HP and smaller

4280 4x3x11.5,  with 1750 RPM motor 5 HP and smaller

4280 4x3x11.5,  with 3500 RPM motor 7-1/2 HP and smaller

Shipping rate for continental USA

$629.00

Add to Cart:
  • Model: 4280S-11-1/2
  • 28000 Units in Stock
  • Manufactured by: Armstrong
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November 20, 2025 by A Reviewer (United States)
“quick reorder,offered alternative filter to delayed Carrier filter”
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November 19, 2025 by Victor N. (Tennessee , United States)
“Helpful customer service.
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New part functioned as expected.
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November 18, 2025 by A Reviewer (United States)
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Manufacturer Info

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