Amtrol Expansion Tanks



Amtrol Therm-X-Trol products

We Can Take the Pressure™

Amtrol invented the thermal expansion tank to absorb expanded water in closed, hot water systems and protect the water heater. Since the beginning, we’ve kept the pressure on our competitors with features they just can’t match; like our patented Turbulator™, antimicrobial liner, patent-pending InSight™ service indicator cap and 50 PSIG precharge.
When your water heater is on the line, we deliver




The One That Started It All™

Extrol expansion tanks accept expanded fluid in closed-loop hydronic systems to control pressure buildup, improve comfort and help reduce energy costs. Nearly seven decades after inventing the first diaphragm expansion tank, Amtrol’s lineup now includes specialty models engineered for modern, high-efficiency systems. None of it would have been possible without Extrol – The One That Started It All™.


Expansion Tank Placement

Therm-X-Trol placement

ST-1 placement

Extrol placement

Resources and Literature

Amtrol Tanks

Amtrol Hydronic Tanks

Commercial Literature

Residential Literature

Extrol ASME Brochure

Therm-X-Trol ASME Brochure

Amtrol ST-1 Sell Sheet

Extrol Residential Brochure

Therm-X-Trol Residential Brochure

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