Bell & Gossett Diaphragm Expansion Tanks

Dependable Pressure Control for Closed Hydronic Systems

Non-ASME pre-charged diaphragm expansion tanks are designed to help manage thermal expansion in closed hydronic heating and cooling systems. Commonly used in residential and light commercial applications, these tanks help maintain proper system pressure, improve performance, and protect system components from excessive pressure buildup.

As water heats and expands, the diaphragm tank absorbs the added volume to help keep the system operating safely and efficiently. A heavy-duty butyl diaphragm separates the system water from the tank’s air charge, helping prevent waterlogging while reducing oxygen-related corrosion.

With flexible in-line or floor-mount installation options, diaphragm expansion tanks provide a practical and reliable solution for supporting closed-loop hydronic systems.

Product Features

- Designed for closed hydronic heating and cooling systems
- Suitable for residential and light commercial applications
- Helps prevent excessive pressure in heating systems
- Supports improved system performance and stability
- Helps reduce oxygen corrosion
- Prevents waterlogging
- Heavy-duty butyl diaphragm separates system water from the tank’s air charge
- Available for in-line or floor-mount installation
- Maximum operating temperature: 240°F / 115°C
- Maximum working pressure: 100 PSI / 689 kPa