To make sure we feel comfort­able in our own four walls, it’s impor­tant to have not just an appro­priate setting, but above all a pleasant room climate. However, vapors from objects, as well as biochem­ical processes such as breathing or sweating, reduce the air quality in homes. The humidity also rises when cooking, show­ering or doing laundry – if there is no adequate venti­lation, mold can grow. This damages rooms and their inhab­i­tants.

These prob­lems can be prevented with effi­cient room venti­lation. But many homes are empty a lot of the time, as the resi­dents are at work or engaged in other activ­i­ties out of the house. However, most venti­lation systems work at constant air flow – even in situ­a­tions where this is not neces­sary at all. So they consume energy unnec­es­sarily. In the event of high activity in the rooms, on the other hand, air exchange is often not suffi­cient to improve the air quality. This is why French manu­fac­turer AERECO has devel­oped demand-based venti­lation. The system adapts its perfor­mance to the use of space and only works when it is really needed.

Fresh air flows into the building through air outlets at the windows (1). In exhaust air rooms, a demand-driven humidity-controlled exhaust air element (2) guides the air into the exhaust air shaft. Hybrid fans on the roof (3) adjust their speed depending on the outside temper­a­tures. (Illus­tra­tion | AERECO)

Sensors control inlet and exhaust air flaps

It works as follows: AERECO sensors measure air quality in the home using several para­me­ters. If the quality drops, the system opens the flaps installed in outside air ducts in the living and sleeping areas, thereby auto­mat­i­cally replacing the required air volume. For example, if the humidity in the home rises, the flaps open more and more fresh outside air is let in. Connected exhaust air elements also work this way in kitchens, bath­rooms and WCs: They extract the air more quickly. 

Support for free venti­lation

AERECO relies on hybrid venti­lation, i.e. the combi­na­tion of free and fan-supported venti­lation. A low-pres­sure fan designed for this purpose gener­ates a constant under­pres­sure in the shaft. If the thermal lift is not suffi­cient, the fan switches on auto­mat­i­cally, thus supporting the venti­lation system. Various hybrid venti­lation systems mounted on the building roof ensure that this is done quickly and effi­ciently: The VBP product family with low air perfor­mance levels of up to 400 m³/h, the VBP+ devices for high air perfor­mance of up to 800 m³/h and the fire-proof fans of the VBP⁺C4 series.

Hybrid venti­lation combines free venti­lation with fan-assisted venti­lation. (Photo | AERECO)

The indi­vidual rotor blades of the VBP low-pres­sure venti­lation unit run parallel to the air flow. This means that the entire free cross-section of the shaft is avail­able, which ensures shaft venti­lation even without mechan­ical support. To drive the fan, AERECO uses an ebm-papst EC motor with sepa­rate commu­ta­tion elec­tronics. Reli­a­bility was crucial when selecting the compo­nents. The motor’s dura­bility was partic­u­larly impor­tant to the company. ebm-papst’s prod­ucts also have a good repu­ta­tion among end customers. The motor circuit board is in a plastic box and the cable’s struc­ture is simple. The elec­tronics box in a sepa­rate loca­tion can be mounted outside the air flow. The connec­tion box can thus be installed in an easily acces­sible posi­tion on the venti­lation unit.

Depending on the outside temper­a­ture, a power supply and control unit controls up to 25 venti­lation units and switches them from the basic speed that prevents freezing in winter to the required speed. A VBP venti­lation unit can venti­late multi-family homes with up to seven stories and can also be mounted on existing shafts.

Maximum power, minimum consump­tion

The VBP+ hybrid venti­lation unit provides an advan­tage in terms of energy effi­ciency. It oper­ates at 35 W with an air perfor­mance of 800 m³/h, reducing energy consump­tion to a minimum. An ebm-papst EC motor also contributes to this. For AERECO, it was very impor­tant to have an effi­cient drive that helps signif­i­cantly reduce energy consump­tion while also oper­ating reli­ably.

With a housing made of galva­nized steel and a matrix of calcium sili­cate that protects the motor, the venti­lation unit can with­stand temper­a­tures of up to 400 degrees Celsius for up to 30 minutes.

The venti­lation system auto­mat­i­cally adapts to the weather condi­tions, ensuring a constant under­pres­sure at all times. The VBP⁺ C4 is also suit­able for smoke in the event of a fire. With a housing made of galva­nized steel and a matrix of calcium sili­cate that protects the motor, the venti­lation unit can with­stand temper­a­tures of up to 400 degrees Celsius for up to 30 minutes.

In use when­ever neces­sary

Thanks to the pres­ence detec­tion and CO₂ or VOC sensors in resi­den­tial areas, the fans are only switched on when air actu­ally needs to be extracted. If the house is empty, the venti­lation system auto­mat­i­cally reduces the air exchange; the fresh air supply and exhaust air flow are then reduced. This saves heating energy, reduces the current consump­tion of the venti­lation units – and ensures good air throughout the house at all times.