How to optimise the costs of a ventilation system for large surfaces with our practical and efficient tips.

When talking about pollution, most people think of smog in big cities or fumes from factories. Few are aware that indoor environments, due to the CO2 produced by crowded areas, the use of office equipment and many other factors, have concentrations of pollutants similar to that of outdoor environments, if not higher. 

This is supported, for example, by a study carried out by the Royal College of Paediatrics and Child Health  and the Royal College of Physicians, which considers the indoor environment to be 5 to 13 times more polluted than the outdoor environment.

Indoor air quality therefore plays a fundamental role in ensuring well-being in workplaces and in general in all closed environments, also bearing in mind that people spend most of their time (up to 90%) indoors. Without proper ventilation and periodic air renewal, the risk is that pollutants (outdoor air pollution and pollen, but also fungi, viruses and bacteria) can reach a concentration that is potentially harmful to health. And since opening the windows and frequently ventilating the rooms is counterproductive when it comes to wasting the heat built up in the rooms, the most immediate and effective solution to this problem is controlled mechanical ventilation (CMV).

How does Controlled Mechanical Ventilation work?

Designed for installation in a single home as well as in much larger commercial or industrial buildings - it can be combined with the main heating and air conditioning systems - controlled mechanical ventilation units are devices that ensure clean indoor air at all times thanks to constant air renewal and filtration. The operating principle is very simple:

A first fan draws in the exhaust air inside the building and expels it outside, while a second fan performs the same process but in reverse, bringing clean, properly filtered air from outside into the rooms. The heat recovery system, which plays a crucial role in this process, is a unit component that enables the efficient recovery of the thermal energy in the stale air and ensures that the inlet air is heated correctly.

Different types of Controlled Mechanical Ventilation systems

In plant engineering there are different types of controlled mechanical ventilation systems, which differ according to the number of units supplying the rooms and whether there is a single alternating flow or two flows.

Decentralised or point-to-point CMV is when a unit is installed for each individual room in the building, whereas centralised CMV is when a single unit is used to ensure air renewal in at least two rooms. The former has the advantage of being less invasive than the latter, as there is no ducting system to connect the unit to the various rooms, just a single hole in the perimeter walls. Centralised CMV, however, ensures the best energy efficiency.

The advantages of Controlled Mechanical Ventilation

In addition to providing major benefits in terms of living comfort, thanks to its unique feature of constantly renewing the air throughout the day, controlled mechanical ventilation is essential in ensuring significant energy saving. Its application is indeed perfect in buildings fitted with state-of-the-art doors and windows that prevent or severely limit heat loss to the outside. As such, opening windows to ventilate the rooms would, especially in cold seasons, waste the thermal energy stored in the building. CMV units, on the other hand, have the unique feature of recovering a significant amount of heat present in the exhaust air that is drawn in and expelled, which is used to heat the air supplied to indoor environments. The result is excellent air quality and perfectly filtered and heated air, which eliminates energy waste.

But the advantages of Controlled Mechanical Ventilation systems are not only energy saving. Here is a short list of other advantages that make this type of solution extremely competitive and suited to all needs:

  • Filtration: the air supplied to the room is filtered through special filters with different degrees of filtration (from coarse to very fine). A process that provides significant benefits to people suffering from allergies and respiratory disorders, and to all people in general.
  • Acoustic comfort: if properly designed and installed, CMV units produce practically no noise. That is not all: avoiding constantly opening the windows prevents external noise pollution from entering the building.
  • Combination with heating systems: Controlled Mechanical Ventilation technology is fully compatible with most heating, cooling and domestic hot water production solutions.

Clivet and Controlled Mechanical Ventilation

IEQ (Indoor Environmental Quality) for residential, commercial and industrial applications is of paramount importance to Clivet. It is no coincidence that over the last few years the company has developed a range of innovative high-efficiency CMV systems that are easy to install and feature various heat recovery technologies (active and passive) and different sanitisation systems.