August 28 2018

Flexible, efficient and safe – why specifiers should choose plate heat exchangers

Paul Sands of Stokvis Energy Systems examines the advantages offered by plate heat exchangers. 

From modern leisure centres and industrial premises, to hotels, apartment blocks, and health establishments wanting to isolate new boilers from ageing pipe systems, plate heat exchangers (PHEs) offer building services professionals a host of technical and practical benefits that are driving their increased use.

In their most basic form, bare plate heat exchangers can be installed along with replacement boilers, taking up very little space within often congested plant rooms. They deliver excellent heat transfer with minimal water content while protecting the primary circuit from potential contaminants present in old pipes and radiators. In addition, they also create a hydraulic break which can prevent the increased pressure from a newly installed pressure set causing leaks on the secondary side.

In a similar manner, plate heat exchangers can be used to convert medium temperature hot water into low temperature hot water, or as the interface between steam circuits and domestic hot water supplies. They can also feature in subsidiary plant rooms; perhaps feeding underfloor heating systems.

Additionally, as energy policy pushes the increased use of heat pumps, solar thermal hot water and other renewable sources – as well as heat networks which might include waste heat – PHEs represent the ideal means of heat transfer

One of the key ambitions in promoting the adoption of communal or district heating schemes is being able to extend them to cover nearby new developments, or exploiting additional heat sources that become available. Again, PHEs are ideally flexible and can have extra plates added to increase their capacity.

The plate sets are easily accessible for maintenance by simply removing the front chassis while the turbulent nature of the water flow through the units combined with an even transfer of heat reduces the tendency for fouling or scale formation.

Thanks to their high energy efficiency and rapid heat transfer characteristics, PHEs have been repeatedly used over the years to update older domestic hot water systems which featured large volume hot water storage, greatly reducing the risk of Legionella or other bacterial growth. Avoiding the need to continually boost the temperature of stored water which is a further benefit.

The high temperature differential on the primary side of the PHE and hence the lower return temp, enables modern boilers to remain in condensing mode for more of the time. The greater the Delta T the smaller the flow rate, which facilitates the specification of smaller diameter primary pipework, as well as smaller primary pumps using less energy.

Stokvis Energy Systems’ Econoplate range presents packaged units with a choice of gaskets and other materials and ancillaries for use in Hot Water Service applications and a host of other diverse applications and with different fluids. Finally, as a fully certified product solution available in a wide range of sizes and outputs, plate heat exchangers are accepted across the world, comply with the pressure equipment directive and all Hot Water Service packaged units are WRAS approved.

For further information on Stokvis Energy Systems, please call 020 8783 3050 or visit www.stokvisboilers.com.