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.

The Refix HW 25 expansion vessel is designed for domestic water systems that are not used in DIN 1988 compliant drinking water installations.

Purpose-built for EN 12828 heating and chilled-water systems, this multifunction sealed-system unit combines automatic expansion control, pressurisation, deaeration and make-up in a single package.

A pressure-step degassing process—using a controlled pressure drop and patented PALL-ring media—removes dissolved gases even at equilibrium. A replaceable butyl bladder stores the expansion fluid at atmospheric pressure. Supplied with Flexvent Super, height-adjustable feet and a weight-capacity sensor.

• All-in-one functionality — expansion, pressurisation, deaeration and make-up
• Pressure-step deaeration with PALL-ring technology
• Replaceable butyl bladder — easy maintenance and long service life
• Delivered complete — Flexvent Super, adjustable feet, weight-capacity sensor

Designed for commercial, industrial and residential sealed LPHW/CHW installations requiring efficient air removal and stable operating pressures.

Engineered for EN 12828 heating and chilled-water systems, Flamcomat FB Auxiliary Vessels provide additional, pressureless expansion capacity to stabilise sealed system pressures.

Used alongside the Flamcomat FG module, the FB vessel stores expansion fluid at atmospheric pressure inside a replaceable butyl bladder. The wider Flamcomat system employs a pressure-step degassing method with patented PALL-ring media for effective dissolved gas removal. Supplied with Flexvent Super and height-adjustable feet.

• Pressureless auxiliary vessel — increases system expansion volume
• Replaceable butyl bladder for easy maintenance
• Atmospheric storage of expansion fluid inside the bladder

Suitable for systems with a maximum operating temperature of 120 °C (note: additional requirements may apply above 110 °C). Bladder maximum temperature 70 °C.

Flamco Flexcon M Expansion Vessel - 100Ltr - 3-6 bar. - Tailored for sealed heating and chilled-water systems, the Flexcon M 100/3.0 [6Bar] is a replaceable-bladder expansion vessel designed to stabilise pressure in accordance with EN 12828.

It excels where static pressure and safety-valve setpoint differ significantly, helping maintain pre-pressure while minimising cycling. Supplied ready to install with a pressure gauge and height-adjustable feet, plus an inspection flange for servicing.

• Replaceable butyl bladder for fast maintenance
• Pressure gauge and height-adjustable feet included
• Inspection flange for internal access
• Robust steel vessel with durable epoxy-powder finish
• Uncoated connection thread for easy, watertight installation

For larger models (12008000 Ltrs), a Flexvent Super can be fitted to enhance air removal.

Built for sealed heating and chilled-water circuits, the Flexcon M [10Bar] is a replaceable-bladder expansion vessel designed to stabilise system pressure in line with EN 12828.

It excels where static pressure and safety-valve setpoint differ significantly, helping maintain pre-pressure while reducing cycling. Supplied with a pressure gauge, height-adjustable feet and an inspection flange for straightforward servicing.

• Replaceable bladder for fast maintenance and long service life
• Delivered ready to install: gauge and adjustable feet included
• Inspection flange for internal access
• Robust steel vessel with durable epoxy-powder finish

Larger Flexcon M models (12008000 Ltrs) can be fitted with a Flexvent Super for enhanced air removal.

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.

The ElbiAC25 GPM 25 Litre Accumulator Pressure Vessel - 25 Ltr - 10 bar. is a Pressure Vessel item. This product is manufactured by Elbi.

The accumulator vessel is a device that fitted into a pressurised water system will provide system water at a pre-set sustained pressure.

Its most common application is to supply systems in which the main supply pressure is too low and a pump is fitted to boost the pressure to an acceptable level.

As system demands take place the accumulator vessel will sustain system pressure by feeding additional water into the system at the required pressure.

This process will limit the number of times the pump needs to start (pump hunting) in order that system pressure remains at the optimal level.

The operating pressure of this is 10 bar.

The accumulator vessel is a device that fitted into a pressurised water system will provide system water at a pre-set sustained pressure. This product is manufactured by Elbi. Its most common application is to supply systems in which the main supply pressure is too low and a pump is fitted to boost the pressure to an acceptable level. As system demands take place the accumulator vessel will sustain system pressure by feeding additional water into the system at the required pressure. This process will limit the number of times the pump needs to start (pump hunting) in order that system pressure remains at the optimal level.

The Elbi AFV 24-16 24 Litre Vertical Accumulator Pressure Vessel - 25 Ltr - 16 bar. is a Pressure Vessel item.

The operating pressure of this is 16 bar.

MikroPro Potable XP Expansion Vessel - 19 Litre Capacity - 10 bar. This range serves heating, chilled and potable (drinking) water systems, with capacities up to 500 Ltrs to suit a wide variety of installations for commercial or residential. This item comes without a wall mount bracket.

Built for hygiene and durability, all internal surfaces in contact with water are corrosion-protected for potable use, and models from 50–500 Ltrs feature a replaceable diaphragm for straightforward maintenance.

• Capacity options: 12–500 Ltrs
• Rated pressure: up to 10 Bar
• Potable-safe construction: coated internal wetted surfaces
• Serviceable design: replaceable diaphragm (50–500 Ltrs)

Vessels are PED 97/23/EC compliant, rated to 70 °C, and supplied with threaded connections and a durable powder-coated finish for long service life.

Built for sealed LPHW/CHW systems, this Airfix Expansion Vessel delivers reliable performance with a tidy, installer'friendly form.

For use in potable water, or fresh-water installations.

The Airfix D expansion vessels operate in such a way that the water flows right through and they are continuously flushed with fresh water from the mains.

This prevents tepid, stagnant water from collecting in the vessel in which bacterial growth could occur.

Therefore, users can be assured of high quality potable water.

Applying an Airfix D expansion vessel to a water heater prevents the opening of the safety group or safety valve each time the potable water is heated.

Engineered for day'to'day plantroom demands, it helps maintain stable operation, protects equipment, and simplifies maintenance.

• Reliable absorption of system expansion
• Factory pre-charge for quick commissioning
• Durable diaphragm construction

Pair with suitable isolation, safety devices and treatment to meet site requirements and best practice.