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.

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.

Flamco Flexcon Expansion Vessel - 110Ltr - 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.

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 3 vessel Mainsboost 130 litre vertical steel system with 22 mm connections are installed directly onto the incoming water supply and under mains pressure fills with water. When the chamber is full the pump reaches a state of pressure equilibrium. The Mainsboost system now has a volume of pressurised water ready for distribution throughout the property.

Mains Liquid Boosting Setup

The Mainsboost 130 litre vertical steel composite with 22 mm connections is installed directly onto the incoming liquid supply and under mains pressure fills with water. When the chamber is full the pump reaches a state of pressure equilibrium. The Mainsboost system now has a volume of pressurised water ready for distribution throughout the property and where required can be supplied with multiple vessels options. 

The 2 vessel Mainsboost 130 litre vertical composite system with 22 mm connections are installed directly onto the incoming water supply and under mains pressure fills with water. When the chamber is full the pump reaches a state of pressure equilibrium. The Mainsboost system now has a volume of pressurised water ready for distribution throughout the property.

The 3 vessel Mainsboost 130 litre vertical composite system with 22 mm connections are installed directly onto the incoming water supply and under mains pressure fills with water. When the chamber is full the pump reaches a state of pressure equilibrium. The Mainsboost system now has a volume of pressurised water ready for distribution throughout the property.

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.

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.

Mains Liquid Boosting Setup

The MAINSBOOST MB 130SV-1 is intended for 'direct on mains' systems (unvented hot water cylinders and combination boilers) where the incoming mains pressure is greater than 2.5 bar. but the flow is insufficient to meet demand.
MAINSBOOST vessel systems do not require an electrical supply and operate silently.

System cold water storage capacity can be expanded simply by adding one or more MAINSBOOST Add-on pumps as required. 
If the incoming mains water pressure is less than 2.5 bar., a MAINSBOOST Charger pump can be utilised in conjunction with the MAINSBOOST vessel system to boost pressure.

The MAINSBOOST MB 130SV-1 features a nominal vessel size of 130 litres and a pressurised cold water water storage capacity of approximately 72 litres.
Each pump is supplied with the unique compact MAINSBOOST Monobloc 22/28mm Upstream Kit (USK) as standard which significantly simplifies installation.

Constructed from an epoxy coated steel body and a highly durable virgin butyl diaphragm, all MAINSBOOST vessels are supplied with a 5 year warranty.

The 2 vessel Mainsboost 130 litre vertical steel system with 22 mm connections are installed directly onto the incoming water supply and under mains pressure fills with water. When the chamber is full the pump reaches a state of pressure equilibrium. The Mainsboost system now has a volume of pressurised water ready for distribution throughout the property.