Amtrol 90 EXTROL Expansion Tank 14.0 Gallon (112-1) Amtrol EXTROL 90 Expansion Tank Features: For use with closed hydronic heating and cooling systems Factory pre-charged to 12 psig Pre-charge should be adjusted to equal minimum operating pressure at tank location Maximum working pressure: 100 psig Maximum operating temperature: 240 F Though product can be mounted horizontally this can decrease the life of the product. Amtrol EXTROL 90 Expansion Tank Specifications: Model Number - 90 Tank Volume (Gallons) - 14.0 Max. Accept. Volume (Gallons) - 11.3 A Height (Inches) - 21 B Diameter (Inches) - 15 3/8 System Conn. (NPTM) - 1/2 Maximum Working Pressure = 100 PSIG Maximum Operating Temperature = 240 F Factory Precharge = 12 PSIG