Founded in 1946 AMTROL has pioneered and revolutionized the hydronic industry with the world’s first pre-pressurized diaphragm expansion tank. This was followed in 1963 with the invention of the first pre-pressurized well tank and in 1967 with the invention of the refrigerant gas cylinder. AMTROL went on to invent the indirect fired water heater in 1980 and the thermal expansion tank in 1991. Throughout our history, AMTROL has been the world leader in the design and operation of the vital mechanical systems that are used to control hydronic heating and to store potable water.
Today, AMTROL products include a comprehensive array of water system solutions for storage, treatment, heating, expansion and flow control serving the residential and industrial markets. Our products are manufactured in the USA at our ISO 9001:2015 facilities in Rhode Island and Maryland.
Hydronic Heating and Chilled WaterExtrol Hydronic Expansion Tanks: Extrol ASME commercial expansion tanks are designed to control pressure in closed hydronic heating systems. Available in diaphragm, partial acceptance bladder and full acceptance bladder designs, these tanks range in size from 8 gallons (30 liters) to 3,963 gallons (15,000 liters). Offered with maximum working pressures up to 300 PSIG (21 bar), Extrol is effective at maintaining positive pressure in a wide variety of HVAC systems.