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Invented in 1984 by Aereco, the humidity sensitive ventilation systems automatically adjust the airflow depending on the room humidity, without electricity. It still regarded as a major technological breakthrough in demand controlled ventilation today.

Working of the humidity sensitive ventilation

Aereco humidity sensitive ventilation systems are principally based upon the modulation of the air cross section – and so of the airflow – at the air inlets and exhaust units level, using an ingenious mechanical sensor which directly drives the shutter set in the air stream (without electricity).

An accurate and reliable automatic sensor

As detector and driver of our humidity sensitive products, the V8 sensor exploits a well-known physical phenomenon: the property of some fabrics to lengthen when humidity increases in the air and to shorten when the humidity level is lower.
On this principle, the 8 or 16 polyamide bands of the sensor activate one or more shutters, thus determining the passage of the air according to the ambient relative humidity rate. The greater the level of humidity, within building, the more the shutters are open. The sensor is isolated from the incoming airflow; it only measures the indoor humidity, without undergoing clogging of the exhaust air discharged through the exhaust units.

Moreover, thanks to a thermal correction applied to the sensor of the air inlets, the opening of the shutters is carried out independently of the external climatic conditions, even when the absolute humidity is low, as in winter.

Moisture, a relevant indicator of the housing pollution

Moisture is a particularly relevant indicator of the need for ventilation in housing. Whether this is produced through activities such as cooking, showering or washing/drying clothes etc. or through metabolic processes such as respiration and sweating, moisture is produced at various times, in different locations, and in variables quantities. In a relatively airtight home without a properly designed humidity sensitive ventilation system, moisture condenses on the colder walls and windows promoting mould growth. This not only has the potential to cause structural damage, but also presents a health risk to the respiratory systems of the occupants*.

By adjusting the airflow with reference to the relative humidity, the humidity sensitive ventilation provides an effective and coherent response to the problem of condensation.

More generally, CO2 (produced by the metabolism) and cooking odours. Consequently, humidity sensitive ventilation also provides a continuous and proportional adaptation of airflow to these pollutants, to better evacuate them.

*As a liquid or vapor, water is a top cause of accidents in the building. If a relative humidity between 40 and 60% is essential for the proper functioning of the respiratory system, extreme moisture proved detrimental to both the building and its occupants.

Humidity control A and humidity control B, what is the difference?

The humidity-controlled MEV, which goes by various names, can come in two forms, known as A or B.

The humidity-controlled MEV A has self-adjusting air inlets in dry rooms associated with humidity-controlled exhaust units in wet rooms.

The humidity-controlled MEV B, meanwhile, offers humidity-controlled air inlets, always associated with humidity-controlled exhaust units.

It should be noted that, in either system, the humidity-controlled exhaust units provide additional activation modes for peak flow such as pull cord or presence.

With its intelligent air inlets, the humidity-controlled MEV B is more efficient than the humidity-controlled MEV A.