Altecnic Eres are able to offer a complete range of expansion vessels to meet the requirements of most heating systems and for use with potable water. The expansion vessels are manufactured to meet the requirements of PED 97/23/EC Directive and BS EN 13831:2007 ‘Closed expansion vessels with built in diaphragm for installation in water’.

Design

Vessels are fabricated by welding the various sections together which results in a very reliable structure suitable for internal pressures up to 10 bar. 

Replaceable bladder.

Aisi 304 stainless steel threaded connection.

Pre-pressurised air chamber with EPDM elastomer bladder.

The internal surfaces of the vessel are epoxy coated, to help prevent bacterial growth and corrosion.

Epoxy coated in white.

Suitable for temperatures up to 100°C, resistant to ethylene or propylene glycol mixtures and has low gas permeability. Altecnic expansion vessels are all tested according to the Pressure Systems Directive.

How It Works

In a closed hot water circuit, the water cannot be compressed so any increase in volume, created by an increase in temperature, has to be accommodated by an expansion vessel. When water is cold, the pre-charge pressure forces the bladder to collapse until the pump is started when the bladder starts to inflate. As the temperature in the system increases, with the associated increase in pressure and volume, the expanded water enters the bladder creating additional volume and lowering the pressure. When the temperature decreases, the pre-charge pressure forces the water from the bladder and back into the main water circuit.