2 Mar 2021
The choice of the right heat exchanger
How to choose the right heat exchanger? By making the right choices to ensure the helthiness of the air!
Today the necessary requirements that a heat exchanger must meet according to VDI 6022 are:
– No contamination of the delivery flow.
– Corrosion resistance.
– Materials that don’t favor bacterial proliferation → for this reason the Recuperator sealan is silicon-free and, confirming the tests carried out, isn’t a site of bacterial proliferation.
– Easy maintenance and cleaning.
Plate heat exchanger
Let’s now see the characteristics of the plate heat exchangers:
– Excellent seal between the two flows.
– Wide range of steps and patterns.
– Up to 100.000 m³/h of air.
– Efficiecy between 50% and 80%
– Low pressure drops → the differential pressure can influence influence the pressure drop because it can
elastically deform the fins of the recuperator if it is too high (>2500Pa).
For hospital applications that require high speed and / or high differential pressure, Recuperator
offers a feature for increased strength (special plate treatment), called OPTION XS. In addition, the
surface in contact with the air must demonstrate strong resistance to corrosion. To comply with
this requirement, the galvanized sheet frame must be coated with an epoxy protection: TV
All plate heat exchanger units in the Recuperator range can be used within hospital facilities and
are “ILH Berlin” certified.
The leakage of plate heat exchangers is very low, depending on the options it can be close to 0%.
Rotary heat exchanger
To limit the leakage between one flow and another, brush seals are mounted on the circumference of the wheel and on the crossbars. In order for it to work effectively, the pressure must be greater with respect to the exhaust. A sufficient overpressure of the fresh air is achieved with a correct position of the fans.
It is also important to consider the position of the fans inside the ventilation unit to have the fresh air side always overpressure. The images below show the possible fan recovery combinations, highlighting the suggested positions.
Find out how this also affects the article SARS-Cov-2 VS HEAT EXCHANGERS
In hospital applications, surfaces in contact with air must demonstrate strong corrosion resistance. The frame of the rotary heat exchanger can be coated with an epoxy protection to counteract corrosion. pplicazioni ospedaliere, le superfici a contatto con l’aria devono dimostrare una forte resistenza alla corrosione.
Cleaning of the heat exchanger can be done through:
– Compressed air in case of dust deposits
– Hor water and detergents in case of greasy deposits
The rotary heat exchanger is more sensitive to the design choices, installation and maintenance of the system, it is therefore reccommended, for hospital applications, to prefer plate heat exchanger.
Where can we see our recovery units in operation?