How does a Flow Through Expansion Vessel Work?

In this blog, we explore in detail the role of a flow through expansion vessel and its role in preventing harmful bacteria build up in potable water systems.  Whilst a flow through vessel can be used effectively on any potable water system they are particularly useful in healthcare, education, hotel, hospitality and other public use settings.

What is a flow through expansion vessel?

Flow through expansion vessels are designed to keep potable water moving through a system in order to prevent any stagnation or contamination. The innovative design encourages flushing through the vessel, greatly reducing the opportunity for clusters to form.

How do flow through vessels work?

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.

How do flow through vessels help to prevent Legionella & Pseudomonas?

When fitted with the PVACC Flowjet valve the vessel is anti-legionella which further assists in the constant movement of water in the vessel to prevent stagnation. The PVACC Flowjet valve is supplied as an optional component with an Altecnic Reflex Flow Through Vessel.

What is a Flowjet Valve?

The Flowjet valve enables 4 functions to be performed easily: -

1. Continuous water flow through the bladder helps to maintain the quality of the potable water by minimising stagnation.
2. Isolation should the expansion vessel need to be removed
3. Drain facility
4. Bypass

What approvals do Altecnic Flow Through Vessels have?

Altecnic Reflex flow through vessels are WRAS approved up to 33 litre capacity, CE marked and come with a 5 year warranty. For information on specific vessels and sizes, please consult the latest data sheet or contact our technical team on 01785218206 or technical@altecnic.co.uk .

Where can I find more information about keeping waters systems safe for public use?

Altecnic works with and are members of a number of professional industry bodies and associations who advocate the importance of keeping water systems safe from the risks of legionella and other harmful bacteria such as:

The Legionella Control Association

The Water Management Society

 The Society of Public Health Engineers

Chartered Institute of Plumbing and Heating Engineers

If you would like to speak to a member of the Altecnic Technical team about our flow through vessels please email technical@altecnic.co.uk .