Thermal expansion occurs when water is heated during non-use periods. The installation of a Pressure Reducing Valve (PRV), Check Valve or Back Flow Preventer "closes" the water system, leaving water with no room for expansion. National Standard Plumbing code: 10.5.7 requires backflow prevention, to prevent backflow into the water main.

Thermal expansion in a closed plumbing system can be damaging, dangerous and costly. Its effects include damage to water heater connections, gas water heater flue tubes, pumps serving washers and dishwashers, leaking faucets, "weeping" of water through the water heater T&P Relief Valve, and noisy water hammer in the pipes.

A properly sized Expansion Tank eliminates these problems, by giving water a place to go when thermal expansion occurs. When a water heating cycle ends, or when any fixture is opened within the system, the impact of thermal expansion is reduced, and water drains out of the expansion tank back into the system.

  • Maximum Working Pressure: 150 PSI
  • Maximum Temperature: 140°F Residential, 180°F Commercial
  • For use with residential and commercial water heaters
  • In-line design, with 3/4" NPTM connection: installs in cold water line of water heater
  • Field-adjustable 38 PSI air charge
  • Drawn-steel tank with 2-coat bonded polymer inner lining
  • Butyl diaphragm, for permanent separation of air and water, with no waterlogging
  • IAPMO Approved
  • 5-Year Limited Warranty
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5 Year Limited Warranty
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