Built for sealed potable hot and chilled water systems in domestic and commercial settings, these Potable Water Expansion Vessels stabilise pressure by absorbing thermal expansion for safe, reliable operation.

A nitrogen pre-charge helps retain set pressure longer, while a single threaded steel connection with plastic insert provides a durable, non-flow-through design. Suitable for central heating, cooling and tap water applications (not for solar collector circuits).

• Nitrogen gas filling for longer pre-charge retention
• Single threaded steel connection with plastic insert (no flow-through)
• Potable use supports domestic hot/chilled water
• Heating & cooling compatible for sealed systems

Designed for long service life with broad operating limits and glycol tolerance for demanding installations.

Grundfos GT-D are maintenance-free double-diaphragm pressure tanks with a capacity ranging from 100 to 450 litres.
The tanks are designed for a maximum operating pressure of 10 bar and a maximum liquid temperature of 90 °C.

The tank is a steel pressure tank with a patented controlled-action CAD-2 diaphragm assembly, pre-charged to 1.4 bar. The tanks have a non-replaceable, chlorine-resistant 100 % butyl diaphragm with a precision-moulded copolymer polypropylene liner for superior air and water separation. The diaphragm assembly seals water in a truly non-corrosive chamber, while the air chamber is sealed with a fixed O-ring and closed cell foam, which provides long-lasting and service-free durability.

The tank is appropriate for drinking-water applications in combination with installations with booster systems, well systems, irrigation systems, thermal expansion, hydronic heating expansion, hydraulic hammer arresting and clean water backwash for ultra-filtration systems. The tank also features: