From the series "Air conditioning, ventilation, heating—solutions, trends 2023"
Modern and ecological construction must meet increasingly stringent building standards, including those for efficient air exchange. A mechanical ventilation system with heat recovery, or recuperation, used in single-family homes, is one of the solutions that will not only help ensure a good indoor climate, but also keep the house warm. What more is worth knowing about it?
According to research, 90% of our time is spent indoors—at home, school or in the office. Fresh air is therefore essential for the proper functioning of our body, as it ensures well-being, health, concentration and better productivity. A mechanical ventilation system allows full control of the air supplied to the rooms and recovery of heat from the air that is generated inside the building. Its main element is the air handling unit—recuperator, while the transport and collection of air is carried out by means of ventilation ducts distributed throughout the rooms.
Air handling unit—ecological, quiet and efficient
The heart of the mechanical ventilation system, the recuperator, can be considered its most important element. What parameters should be paid attention to during its selection?
The best air handling unit is one that operates in a way that is unnoticeable to the user. When choosing a recuperator, therefore, you should pay attention to its volume, which is described in decibels (dB). This is all the more important if the air handling unit is located close to or in rooms we use every day, such as the kitchen, living room or bathroom.
Modern air handling units should be equipped with energy-efficient fans. Salda units have EC-type fans from German manufacturers EBM-PAPST, ZIEHL-ABEGG, which have a long service life (more than 15 years). They consume only 0.22 watts to transport 1 m³ of air per hour.
The air handling unit is designed to provide a continuous supply of fresh air. Contaminated air from the outside, thanks to the appropriate filters and their highest parameters (F7 class filters), is cleaned of pollen and insects. The filters also prevent and protect residents from dust mites, dust and mold.
© Lindab Polska
Regardless of changing external conditions such as temperature, the unit should work without interruption and adapt to the prevailing internal conditions. A good air handling unit should also return to operation after a temporary power outage.
Type of heat exchanger
A recuperative air handling unit can be equipped with a counterflow or rotary heat exchanger. The task of the exchanger is to heat the air extracted from outside with the air taken from the premises. Air is pumped into the exchanger by means of independent supply and exhaust air streams that do not mix with each other, guided in adjacent ducts. In the case of counter-current exchangers, the efficiency of this process can be above 90%, while rotary exchangers have a maximum heat recovery efficiency of 82%. An unquestionable advantage of this solution is the partial moisture recovery, which reduces the level of dry air in the rooms, which has a positive effect on the indoor climate.
Air humidity andCO2 sensors
With humidity sensors placed in the rooms, the air handling unit will react and adjust its operation according to the conditions in the room. For example, when the humidity in the room begins to increase (during bathing or cooking)
Clear and intuitive controller
Ease of control of the device and the possibility of installing the controller both in the housing of the unit and anywhere in the house is another parameter worth paying attention to. It is worth installing it in a publicly accessible place, where we visit every day, so that we can keep track of messages and react to them, for example, about the need to change filters. Such a possibility is provided, among others, by the recuperator of the British brand Vent-Axia, model Kinetic Advance.
© Lindab Polska
Efficient and energy-efficient air handling units for homes are offered by Salda and Vent-Axia brands, which are famous for their high-end equipment. Experts from Lindab Polska, the exclusive distributor of both brands in Poland, will help you select the right models.
You can learn about how an air handling unit works from the video „Recuperation at home”. See how it works!
Ventilation ducts—manifold system or SPIRO pipes?
A mechanical ventilation system can be made in at least two ways. The first way is to use the SPIRO system, which is based on galvanized steel ventilation ducts. The second involves the use of a manifold system made of HDPE pipes, designed for ventilation.
Direct Vent manifolds—distribution in the insulation layer on the ceiling
© Lindab Polska
Manifold system when space is of the essence
The manifold system of mechanical ventilation is a system in which air is supplied and exhausted to rooms through ventilation valves in expansion boxes. The boxes are connected by HDPE polyethylene ducts to supply and exhaust manifolds. The ducts are usually run in the layer of insulation on the ceiling above the rooms or in the layer of the false ceiling, so they do not take up much space and, unlike the SPIRO system, do not require additional G-K development. The cost of the manifold system is usually lower than that of a system based on SPIRO steel ducts, and the installation time is significantly shorter.
Lindab Spiro pipes—installation under a suspended ceiling
© Lindab Polska
SPIRO system, when we bet on efficiency and like silence
Ventilation system based on SPIRO pipes needs much more space for installation. This is primarily due to the larger pipe diameters of 100 even up to 200 mm. In addition, a system built based on SPIRO pipes cannot be hidden in the insulation. It is necessary to incur additional costs associated with local G-K developments and thus lowering the suspended ceiling by about 30-35 cm. However, the SPIRO system has many advantages. First, it has lower supply and exhaust resistance than a manifold system, which translates into lower energy consumption by the recuperator and its overall efficiency. This makes it definitely more economical in terms of operation. Secondly, the operation of a ventilation system built with SPIRO pipes is quieter. It is also worth remembering that when installing ventilation in the attic, it is much easier to insulate SPIRO-type ducts than ventilation built on the basis of a manifold system.
Both the proprietary Direct Vent manifold ventilation system and SPIRO pipes can be found in the offer of Lindab Poland.
For more information, visit the company's Lindab Sp. z o.o. page on the PdA portal.