Reliance – Aquasystem AR35 35 Litre Potable Expansion Vessel XVES050070 – Transit Damaged

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Aquasystem 35 Litre Potable Expansion Vessel XVES050070 – Transit Damaged

Customer notice: This vessel has been damaged in transit but does not effect the operation of the product – please see photos for details. This product comes with no warranty, and we do not accept returns; sold as seen.

AR35 Aquasystem replaceable membrane Potable Water Expansion Vessels.

Product: White 35L Vessel
Per-set Pressure (bar): 3
Max Pressure (bar): 10
Height: 440mm
Diameter: 365mm
Connection: 3/4″ MBSP
Code: XVES050070

All Aquasystem expansion vessels are supplied with a replaceable membrane, which separates the water and air, to prevent contamination of the water system, corrosion of the expansion vessel or pressure loss in the water system.

The main purpose of an expansion vessel is to compensate for the increase in volume of water due to the varying water temperatures in hot water or heating systems. When water is heated it expands and as water is not compressible this increased volume will create a rise in pressure within the system. As an example, water being heated from 0°C-100°C will increase by approx 4.5%.

The expansion vessel allows for this extra space, as when water temperature increases the membrane inside the vessel inflates to allow the water to fill the vessel. The membrane will continue to expand until the system reaches its maximum temperature. Once this has been reached the membrane will be fully inflated and takes up the capacity of the vessel shell. Gradually the temperature will drop, which will in turn decrease the volume of water. Due to the pressure from the pressurised air surrounding the membrane, water will start to exit the vessel until the membrane is deflated.

Options Include:

  • Reliance Aquasystem  Replaceable Membrane 2,8,12,18,24 Litre Heating Expansion Vessel
  • Reliance Easifit Sealed System Kit
  • Exansion Vessel Mounting Bracket



Stainless steel bolted flange prevents corrosion.

Extra wide membrane opening prevents noise caused by restricted flow.

Internal membrane preventing water contact with the steel shell, stopping internal corrosion.

Vessel can be serviced without being removed due to replaceable membrane.

Vessel has pre-charged valve for topping up air pressure.

Vessel Size Guide:

Vessel Capacity:Vessel Dimensions:
2 LitreHeight: 250mm Diameter: 110mm
8 LitreHeight: 316mm Diameter: 200mm
12 LitreHeight: 295mm Diameter: 280mm
18 LitreHeight: 430mm Diameter: 280mm
24 LitreHeight: 489mm Diameter: 280mm
35 LitreHeight: 440mm Diameter: 365mm

Additional information

Weight3.5 kg



Manufacturers Code



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