Wessels Bladder Expansion Tanks

Wessels bladder expansion tanks are required in a closed loop heating or chilled water HVAC system to absorb the expanding fluid and limit the pressure within a heating or cooling system. A properly sized expansion or compression tank will accommodate the expansion of the system fluid during the heating or cooling cycle without allowing the system to exceed the critical pressure limits of the system.

Information:

• Wessels NLA Series (ASME) Bladder Expansion Tank Brochure
• Wessels NLA 35-800L Series (ASME) Bladder Expansion Tank Submittal Sheet
• Wessels NLA 35-800L Series (ASME) High Pressure Bladder Expansion Tank Submittal Sheet
• Wessels NLA 1000-1500L Series (ASME) Bladder Expansion Tank Submittal Sheet
• Wessels NLA 1000-1500L Series (ASME) High Pressure Bladder Expansion Tank Submittal Sheet
• Wessels NVA 85-800L Series (ASME) Bladder Expansion Tank Submittal Sheet
• Wessels NVA 1000-1500L Series (ASME) Bladder Expansion Tank Submittal Sheet
• Wessels NLAP Series (ASME) Bladder Expansion Tank Submittal Sheet
• Wessels NL Series (Non-ASME) Bladder Expansion Tank Submittal Sheet

The expansion tank uses compressed air to maintain system pressures by accepting and expelling the changing volume of water as it heats and cools. Some tank designs incorporate a diaphragm or bladder to isolate the expanded water from the pressure controlling air cushion, which is pre-charged at the factory and can be adjusted in the field to meet critical system requirements. The design and operation of this style of expansion tank allows the designer engineer to reduce tank sizes up to 80%.