Xylem-Bell & Gossett ASME Pressure Expansion Tank

The Xylem-Bell & Gossett ASME Pressure Expansion Tank is a pre-charged diaphragm-type pressure vessel for closed hydronic heating and cooling systems. It is also called a Series D expansion tank. It absorbs the expansion of system water as temperature changes and keeps system pressure steady across operating conditions.

Key Features:

• ASME-rated pressure vessel, designed and built to ASME Section VIII, Division 1
• Pre-charged diaphragm design with a heavy-duty butyl rubber diaphragm that separates system water from the tank's air charge, which prevents waterlogging
• Carbon steel shell with a forged steel system connection
• Helps reduce oxygen corrosion and supports overall system performance
• Can be installed horizontally or vertically
• Seismic restraints and sight glass options are available for the Series D line
• Intended for closed-loop hydronic systems, not for potable water systems

Bell & Gossett, a Xylem brand, builds these tanks for commercial, industrial and large residential heating and chilled-water systems. They help protect boilers, pumps, piping and other system components from pressure swings.