Dubai, UAE, 7 May 2018: As part of its leadership workshop series, Eurovent Middle East hosted a technical seminar on air-handling units (AHUs), on April 30, 2018, in Dubai.

At the seminar, industry representatives highlighted the fundamentals of AHUs and energy-saving strategies, while increasing indoor air quality (IAQ), fan technology, residential applications and certifications.

Highlighting the importance of fans in an AHU, Martin Lenz, Team Leader R&D Fire Protection, Filters and Air Handling Units, TROX (Germany), said, “One of the main components in an AHU is the fan, and without the fan, there is no ventilation.”

Further explaining the elements of the plug-fan, Lenz added that the four openings around the fan create a housing for the unit, which improves its efficiencies. “Although it depends on the characteristic curve of the fan and where the duty point is but around five per cent points can easily be achieved only by reducing the air,” Lenz said.

Highlighting a strategy on controlling the airflow behaviour in the ducts, Lenz added that a silencer could be placed in the centre of the ducts, which could improve the fan efficiency. Lenz also pointed out that while the selection criterion of AHU components is critical, implementation of smart controls would significantly contribute towards acquiring of quality technical data, which would result in reducing the usage of energy and better performances of the systems.

Sharing strategies on room relative humidity (RH) management, Arun Diwakar, Assistant Manager – Business Development, Desiccant Rotors International, suggested that there are four available options, which are: (1) rotary passive desiccant air-to-air heat exchanger coupled with dehumidification coil; (2) rotary passive desiccant air-to-air heat exchanger coupled with dehumidification coil and wrap around heat pipe; (3) rotary passive desiccant air-to-air heat exchanger coupled with dehumidification coil and (4) sensible air-to-air heat exchanger and rotary passive desiccant air-to-air heat exchanger coupled with dehumidification coil and passive dehumidification wheel.

Speaking on features of EC fans technology for AHUs for new-build or retrofit applications, John Fernandez, Managing Director, ebm-papst Middle East, said that the fans are plug-and-play air movement systems, they are highly energy-efficient and are maintenance-free with long service life.  He further added that they are built with integrated controls and networking capabilities.

Explaining the benefits of the technology, Fernandez added that the significant advantage of the solution is its high efficiency and low heat losses, and the motors are up to 90% efficient.

Speaking on the combination of variable refrigerant flow (VRF) systems with fresh air handling units (FAHUs) in the residential segment, Utpal Joshi, Head of VRV DX Consulting Sales, Daikin Middle East and Africa, said: “Some of the challenges faced by contractors are that the equipment like the AHUs and controls come from different sources, which makes the integration very difficult.  The ideal solution would be plug-and-play systems, and it is important to consider sourcing the entire system, including the controls, from one vendor or manufacturer.”

Speaking on the certification of air filters, Dr Nodirjon Rasulov, Business Development Manager and Indoor Air Quality Specialist, Camfil Middle East, said: “We need a global standard that is recognised easily. The new ISO16890 is based on the correct pollution levels so that the filter selection for the AHU can be made accurately.”

Explaining the dangers of particulate matter, Dr Rasulov said that while particulate matter (PM) of 50 microns are visible to the naked eye; however, any PM below 50 is difficult to see with the naked eye, which can be a severe health hazard. “PM 10 can enter the throat, while PM 5 can enter the lungs and PM 1 can enter the bloodstream, causing cardiovascular diseases.”

Highlighting the importance of certifications, Brian Suggitt, Chairman, Eurovent Middle East and Managing Director, Systemair Middle East, said that the Eurovent certified performance gives a level of confidence for manufacturers to assure customers that the AHU unit is built correctly, with quality components. Suggitt added that the authenticity of the Eurovent certifications could be checked on Eurovent’s website.