The AMTROL FILL-TROL® system consists of a specially adapted EXTROL® pre-pressurized, diaphragm-type expansion tank, and the FILL-TROL, a specially designed, automatic, fill valve.

• Provides accurate system make up
• Eliminates need for a separate, automatic fill valve
• Fully adjustable up to a maximum working pressure of 100 psig
• Factory pre-charged to 12 psig; tank pressure controls system fill