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Amtrol ST-12 Thermal Expansion Tank

by Amtrol
In stock
Original price $68.79 - Original price $68.79
Original price
$68.79 - $68.79
Current price $68.79
Size: 4.4 Gallons

Nothing is more reliable than the Amtrol ST-12 Thermal Expansion Tank. This essential is built with high-strength steel and heavy-duty butyl and keeps your home water pressure in check by absorbing expanded water in closed hot water systems.

Key Features: 

  • Antimicrobial liner neutralizes bacteria on contact
  • Patented Turbulator water circulation device
  • Strongest tank design featuring deep-drawn steel and multi-dome construction
  • Heavy-duty butyl forms a thick diaphragm
  • Projection welded air stem to reduce leaks


Shell: High-strength steel
Diaphragm: Heavy-duty butyl NSF/ANSI 61
Liner: Antimicrobial
Air Valve: Projection welded
Air Valve Cap: Patented InSight Indicator Cap
Factory Precharge: 50 PSIG for in-line models, 40 PSIG for stand models
Max. Operating Temperature: 200º F (93º C)
Max. Operating Temperature for ST-1: 140º F (60º C)
Max. Working Pressure: 150 PSIG (10.3 bar)
Warranty: ST-1 through ST-12: 7-Year Limited, ST-25V through ST-210V: 1-Year Limited

Benefits and Advantages: 

The Amtrol Thermal Expansion Tank is designed to prevent excessive water and reduce damage to valves and plumbing fixtures at home.

Usage or Application: 

Applications include closed, potable hot water systems to control pressure build-up and protect the water heater. It also accepts expanded water as a system temperature rises and returns hot water when demand occurs.

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Amtrol ST-12 Thermal Expansion Tank