GETTING THE MAXIMUM FROM A VENTILATION SYSTEM WITH ELTA
David Millward, Group Product Manager at Elta Group, explains some key practical considerations for people installing ventilation systems.
Renewed attention to the air we breathe has highlighted the importance of good indoor air quality (IAQ). This is especially true in public spaces such as offices, shopping malls, schools and a whole range of other buildings, which are increasingly responsible for improving IAQ.
Ventilation contractors have a vital role to play in this task. This requires an understanding of how to achieve good IAQ, but also a general knowledge of some of the key considerations that can make a significant difference to the effectiveness of the system.
Define fresh air
With so much attention surrounding IAQ on the introduction of “fresh air”, we first need a better understanding of what this term means. This applies to everyone involved in the ventilation supply chain, from government to manufacturers, contractors and even the general public.
As it stands, there is a general misconception that “fresh air” is simply that which is brought in from the outside. However, this does not go far enough and, in urban settings in particular, the air that is introduced into the building can often contain high levels of pollutants.
Amendments to Parts L and F of the Building Regulations are on the horizon which will aim to provide a more concrete definition and promote better IAQ control in buildings. Contractors should make sure to keep abreast of changing legislation, as this is likely to impact the systems they install in the months and years to come.
Noise and vibration reduction
When it comes to the installation itself, an often overlooked factor in ventilation is noise, and it is often too late by the time it is noticed. Providing a comfortable indoor atmosphere goes beyond air quality, and this is where contractors can add value to their work.
For example, duct noise can be reduced by using attenuators (also useful for airborne noise) or by using lined fan types and duct liner. Structural noise, on the other hand, can be reduced by isolating the fan from the structure and duct. Working to minimize fan noise helps distinguish a good installation from a good one, and can be especially important in quieter places, like a restaurant or library.
Vibration control is also essential to the overall efficiency of a system, as this will contribute to noise as well as user comfort. A fan will inevitably vibrate, which can reverberate through the structure it is mounted on. Vibration isolators are the ideal solution to this problem and should be chosen to provide the minimum deflection required.
Care should also be taken to ensure that vibration isolators are suitable for the fan and the environment it will be operating in, and that flexible duct connectors are available to help reduce noise and vibration. These are just a few of the many options available to entrepreneurs.
Flexible ducts can be a fan’s worst enemy because they introduce resistance into the system, which means you have to use much higher pressure and power output. A common problem is that people incorrectly use a lot of flexible ducts in a roof space, buying say 10m when they really only need 3.5m and, instead of cutting it at the waist, creating a snake shape that puts extra pressure on the fan.
This helps to reduce airflow, increasing the risk of poor ventilation and ultimately contaminants, viruses and colds etc. – something the population is hyper aware of in the current climate. For this purpose, rigid ducts should be used whenever possible, with flexible ducts only used for the final connections. It is also recommended to make sure that all ducts are tensioned.
A reliable partner
Ventilation contractors are often cited by their customers, not only for their ability to install high quality systems, but also for being a wealth of knowledge on all things air quality. Now more than ever, understanding how to deliver good IAQ is a valuable asset, hence the importance of keeping abreast of the latest developments and the most efficient ways to install products.