Eastman 2.1 gal. Thermal Expansion Tank

The Eastman 2.1 gal. Thermal Expansion Tank is engineered for use with gas, oil, or electric direct-fired residential water heaters and hot water storage tanks. By absorbing the increased water volume created during thermal expansion, this tank helps maintain balanced system pressure and prevents unnecessary pressure relief valve discharge. Constructed with a heavy-duty steel outer shell, this field-adjustable expansion tank features an FDA-approved butyl rubber diaphragm and a durable brass inlet connection. The internal expansion membrane eliminates air-to-water contact to prevent corrosion and support long system service life.