Built for sealed heating (EN 12828) and chilled-water systems, Flexcon Premium Expansion Vessels stabilise system pressure by absorbing thermal expansion so plant runs safely and efficiently.

A new TPO (thermoplastic polyolefin) diaphragm on 1235 Ltrs models delivers high flexibility and extremely low permeability, helping the pre-charge hold for longer. Lighter construction cuts material use and transport emissions; packaging is FSC-certified to reduce CO₂ impact.

• Sustainable design lighter TPO membrane uses up to 50% less material
• Long service life 15-year warranty
• Low permeability pre-charge pressure maintained for longer
• Heating & cooling suitable for LPHW and CHW installations

Vessels comply with EN 13831 and the Pressure Equipment Directive 2014/68/EU. Red epoxy powder coating (RAL 3002). Flexcon Premium 3580 are supplied with feet and a mounting kit.

Flamco Flexcon Expansion Vessel - 300Ltr - Engineered for EN 12828 heating and chilled-water systems, this Expansion Vessel stabilises sealed system pressure by absorbing thermal expansion in LPHW/CHW applications.

Maximum working pressure: 10.0 bar.

Vessels in accordance with EN13831.

Suitable for systems with a maximum system temperature of 120 °C.

Minimum/maximum temperature diaphragm: -10 / 90 °C.

Suitable for addition of glycol-based anti-freeze up to 50%.

A flexible rolling diaphragm with a ribbed profile prevents sticking and encourages inflow at the slightest pressure rise, while a nitrogen pre-charge helps maintain set pressure longer. The uncoated connection thread supports quick, watertight installation.

• Rolling-diaphragm design for smooth expansion control
• Nitrogen pre-charge for extended pre-pressure retention
• Top-quality steel with epoxy-powder finish
• Factory tested for reliability

Built for long service life in domestic, commercial and industrial plant rooms, with continuous medium temperatures from −10 to 70 C.

Purpose-built for solar thermal circuits, the Flexcon Solar 8/2.5 [8Bar] expansion vessel supports sealed systems in line with EN 12828, keeping pressure stable in high-temperature applications.

A preformed butyl rolling diaphragm with extremely low permeability helps retain pre-charge, while a nitrogen fill limits corrosion and pressure loss. The clench ring clamps the diaphragm evenly to prevent damage, and a ribbed profile avoids sticking for instant inflow. An uncoated connection thread aids watertight installation; the steel vessel is finished in a gleaming epoxy-powder coat and factory tested.

• Solar-ready expansion vessel for sealed systems
• Butyl rolling diaphragm with very low permeability
• Nitrogen pre-charge for longer pressure stability
• Clench ring construction for a robust, uniform seal

For 880 Ltrs models: both halves are coated before assembly to protect the clamp ring, and the nitrogen valve is countersunk and covered. Continuous medium temperature range −10 to 110 C.