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 500 Litre Vertical Accumulator Pressure Vessel- 500 Ltr - 8 bar. is a Pressure Vessel item.

The operating pressure of this is 8 bar.

The Refix DE 500 diaphragm expansion vessel is designed for water supply installations that are not subject to DIN 1988 requirements, making it suitable for specialist systems such as fire extinguishing installations, service water systems

The Reflex N 500 diaphragm expansion vessel is designed for sealed heating and cold water systems, providing reliable pressure control in closed-system installations.

Zilmet Ultra-Pro Vertical Expansion Vessel - 10 Bar. - 300Ltr Zilmet ULTRA‑PRO pressure vessels are designed for high‑performance potable water and booster systems where reliability and.

Zilmet Ultra-Pro Vertical Expansion Vessel - 10 Bar. - 500Ltr Zilmet ULTRA‑PRO pressure vessels are designed for high‑performance potable water and booster systems where reliability and.

Zilmet Ultra-Pro Vertical Expansion Vessel - 16 Bar. - 500Ltr Zilmet ULTRA‑PRO pressure vessels are designed for high‑performance potable water and booster systems where reliability and.

Zilmet Hydro-Pro Vertical Expansion Vessel - 10 Bar. - 500Ltr Zilmet HYDRO‑PRO pressure vessels are designed for potable water and booster systems where stable pressure and efficient pump.

Zilmet Cal-Pro Vertical Expansion Vessel - 4 Bar. - 18Ltr Zilmet CAL‑PRO expansion vessels are designed for sealed heating systems to absorb thermal expansion as water temperature increases.

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 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.

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.

The HeatWave Vessel - Inline - 18Ltr is a Pressure Vessel item.

The HeatWave™ series hydronic expansion tanks provide quality protection for closed loop hydronic heating systems from excessive pressure due to thermal expansion.

Easy to install and featuring an incorporated hex nut connection, HeatWave™ tanks feature an air chamber sealed with a brass air valve and O-ring sealed air cap.  developed to be supported by either system piping, wall-mounted bracket (inline models) or be freestanding (vertical model with base), the HeatWave™ has a maximum working temperature of 99° C / 210° F .

The operating pressure of this is 6 bar.

• Diaphragm design
• Patented Stainless Steel (vertical models) or chromed steel (inline models) water connection

• Two-part polyurethane, epoxy primed paint finish
• Leak-free, O-ring sealed air valve cap
• Maintenance Free

Includes & Benefits

The PressureWave Vessel - Inline - 18Ltr is a Pressure Vessel item.

• Booster systems
• Well systems
• epoxy primed paint finish
• Leak-free, O-ring sealed air valve cap

Grundfos GT-H are maintenance-free multi-purpose pressure tanks with a capacity ranging from 2 to 100 litres.
The tanks are designed for a maximum operating pressure between 10 and 16 bar and a maximum liquid temperature of 90 °C.

The tank is a steel pressure tank made of a virgin propylene liner. The tanks have a non-replaceable FDA-approved high-grade butyl diaphragm, which is pre-charged with compressed nitrogen (1.9 bar).

To ensure long-lasting durability, the diaphragm and liner are both reinforced in specific wear areas. All internal parts, including the air valve, are rounded to prevent piercing of the diaphragm in extreme conditions. The water connection uniquely provides a dual water and air seal ensuring a completely leakage-free pressure tank. Combined with booster and irrigation systems as well as thermal expansion and hydraulic hammer arrestors, the tank is appropriate for drinking-water and grey-water applications. It provides optimised comfort and a patented stainless-steel water connection. The tank also features:

The Grundfos GT pressure tanks are long-life tanks ideally suited for controlling the pressure in domestic as well as  industrial applications in cold-water (drinking-water) systems.

GT-U-500 PN16 G11/2 V (coated flange)

Grundfos GT-U are bladder pressure tanks with a capacity ranging from 8 to 3000 litres. The tanks are designed for a maximum operating pressure between 10, 16 and 25 bar and a maximum liquid temperature of 70 °C. The tanks are approved for drinking water.

The tanks are steel pressure tanks, with non-toxic butyl rubber bladder enclosed by compressed nitrogen.

A pressure tank ensures controlled pressure in the water supply and thereby limits the switching frequency of the pump unit in case of low water consumption or loss due to leakage. This ensures increased comfort in your installation by limiting the start and stop frequency of your pump. It also creates a more stable assembly by compensating for pressure drops when a tap is opened, while reducing problems with water hammer in the pipes.