Amtrol 389751 Extrol EX-3000-100 Combination Expansion Tank Kit 30 Gallon

Product Description

The Amtrol 389751 Extrol EX-3000-100 is a 30-gallon combination expansion tank kit designed for closed-loop hydronic heating systems, chilled water systems, and residential boiler applications. This in-line combination kit includes an air purger and automatic float vent, making it a complete assembly for controlling pressure buildup in sealed hydronic loops. HVAC technicians and plumbing professionals rely on Extrol expansion tanks to absorb the thermal expansion of water as it heats and cools within a closed system. Without a properly sized expansion tank, pressure spikes can damage boilers, pumps, valves, and other system components. The Amtrol 389751 addresses this by accepting expanded fluid and maintaining stable system pressure throughout operating cycles. The tank features deep drawn steel construction with multi-dome design, giving it one of the strongest tank bodies available in this product class. The heavy-duty butyl and EPDM diaphragm is among the thickest in the industry, built to withstand repeated thermal cycling over years of continuous service. A projection-welded air stem helps eliminate leaks at the air charge connection, and the patented InSight Service Indicator Cap allows technicians to quickly check tank condition during routine maintenance without removing the unit from the system. The inlet and outlet connection is 1-inch male threaded, compatible with standard hydronic piping configurations. The tank carries a pressure rating of 100 PSIG and a temperature rating of 240 degrees Fahrenheit, suitable for most residential and light commercial hydronic heating and chilled water applications. The factory air charge is set at 12 PSIG. This product is lead-free and manufactured in the USA to ISO 9001 quality standards. The EX series from Amtrol has been the benchmark for diaphragm expansion tanks since the category was invented, and the 389751 continues that legacy with a combination kit format that simplifies installation and reduces the number of separate components a technician needs to source.

• Deep drawn steel body with multi-dome construction for maximum tank strength and durability
• Heavy-duty butyl and EPDM diaphragm rated for continuous hydronic service up to 240 degrees Fahrenheit
• Includes integrated air purger and automatic float vent for a complete combination kit installation

Product Highlights

The Amtrol 389751 Extrol EX-3000-100 delivers a complete 30-gallon expansion tank solution for closed-loop hydronic and chilled water systems, combining a heavy-duty diaphragm tank with an air purger and automatic float vent in a single lead-free, USA-made kit rated to 100 PSIG and 240 degrees Fahrenheit.

Product Information

Standard Information

• Brand: AMTROL
• Manufacturer Part Number: 389751