Microclimate in Rooms Equipped with Decentralized Façade Ventilation Device

Abstract

Many building are characterized by insufficient air exchange, which may result in the symptoms of sick building syndrome (SBS). A large number of existing buildings are equipped with natural ventilation, whose work is disturbed by activities going to energy-saving. The thermomodernization activities are about mounting new sealed windows and laying thermal isolation, which reduces the amount of infiltrating/exfiltrating air. In many cases, the mechanical ventilation cannot be used due to a lack of a place in building or architectural and construction requirements. One of the solutions to improve the indoor microclimate is the decentralized façade ventilation. In the article, the internal air parameters in an office room equipped with decentralized façade ventilation device were analyzed. The room was equipped with a decentralized façade unit, which cyclically supplied and removed air from the room. The time of the supply/exhaust was changed to 2 min, 4 min, and 10 min. The temperature and the humidity of the indoor air and the outdoor air and the concentration of carbon dioxide inside the room were measured. The analysis showed that despite the lack of a heater in the device, the air temperature in the workplace and in the central point of the room was in the range of 20–22 °C. The air humidity was in the range of 27–43%.

Review of IAQ in Premises Equipped with Façade–Ventilation Systems

“…The reduction of CO2 concentration was also confirmed by others in their studies [142]. On the other hand, the analysis [110] of the influence of the supply/exhaust cycle length on the CO2 concentration showed that for each cycle length, throughout the entire measurement period the carbon dioxide concentration did not exceed the value of 800 ppm, which means that the premises met the requirements of ASHRAE [1] regarding air The analysis of the air exchanges achieved by the unit with a dampers system [135] showed that, for both the 2-min supply/exhaust time and the 10-min time, the air exchange was sufficient for an office premise. In addition, the analysis of changes in the mean value of carbon dioxide concentration over a 30-min period showed reductions in the analysed parameter ( Figure 9).…”

“…The reduction of CO2 concentration was also confirmed by others in their studies [142]. On the other hand, the analysis [110] of the influence of the supply/exhaust cycle length on the CO2 concentration showed that for each cycle length, throughout the entire measurement period the carbon dioxide concentration did not exceed the value of 800 ppm, which means that the premises met the requirements of ASHRAE [1] regarding air On the other hand, the analysis [110] of the influence of the supply/exhaust cycle length on the CO 2 concentration showed that for each cycle length, throughout the entire measurement period the carbon dioxide concentration did not exceed the value of 800 ppm, which means that the premises met the requirements of ASHRAE [1] regarding air quality in offices ( Figure 10). There is a visible increase in the concentration of carbon dioxide upon entering the user's room.…”

“…They are already the main energy-consuming sector [104][105][106][107][108]. Heating, ventilation, and air conditioning (HVAC) systems alone account for 40-60% of a building's energy needs [109][110][111][112], and the ventilation systems themselves account for 20-30% [113]. With this in mind, in order to globally reduce energy consumption and CO 2 emissions, old buildings should be modernised [114][115][116][117], and also take reduction energy and CO 2 emissions into account in the risk assessment of project management [118,119].…”

“…In the second case, we have systems with a reversible fan, that alternately in one cycle supplies the air, and in the next cycle exhausts the air to the outside [134] (Figure 6). Another solution are devices with which the cyclical supply and exhaust are affected by changing the dampers system [110,135] (Figure 7). The authors, examining solutions without a heat recovery exchanger [136], indicated the need to heat the air due to the risk of Figure 5.…”

“…Decentralised façade ventilation unit with dampers[110]; (1) fan flowing the air constantly in one direction; (2) inflow/outflow grate; (3-6) dampers; (7-10) ducts; (11) intake/outtake.…”