Since the energy-crisis of the 70’ies, the trend goes to energy-saving constructions, that have strongly changed our way of building. The development of highly insulated houses in combination with manual window-airing leads to problems concerning a good q

Gas phase filters have been installed within the air handling unit of an HVAC system feeding 100 %fresh (outdoor) air to an office building. The filters efficiency for ozone (O3) and nitrogen oxides (NO2and NO) has been measured continuously over a one year period as function of time and outdoor airparameters (temperature, relative humidity). The results show that the filters efficiency varies alongtime and depends on temperature and relative humidity of air.

In this paper three real-world air-handling system problems are examined : the issues are discussed, troubleshooting techniques, solutions and lessons learnt are presented. The importance of design-phase integration of components is thus illustrated.

Suppliers of heating, venting and air-conditioning products have leant on metalforming technology to pump out products that perform at higher levels of energy efficiency. In this paper three recent successes are presented of the leaders in that field :TRANE, RHEEM and YORK companies .

A methodology for studying HVAC filter loading and subsequent microorganism removal is presented in this paper. First, the test facility used to challenge the filter media is discussed, then nine loading tests have been conducted , three for each of the three viruses, for the validation of the facility. Finally the results and conclusions are presented.

This paper focuses on the relations between ventiliation systems, indoor air quality and energy consumption. Several strategies are pointed out by which at the same level of energy consumption, the indoor air quality is improved or at the same level of indoor air quality, the energy consumption is reduced. Thus proper ventilation methods are important for the total energy efficiency of buildings.

For that study , an indoor contaminant behavior prediction method has been developed. The contaminant model has been integrated within the whole building simulation environment ESP-r, then validation studies were conducted. In this paper the authors insist on the importance to have a global look at contaminant behaviour, errors could occur if spatial and temporal temperature variations were not included in the prediction of contaminant levels.

Many of the dedicated outdoor air systems designed and installed today are suboptimal. The aim of this paper is to discuss the ways to optimize their design in order to lower both their installed cost and energy use.

In this paper the performance of a computer simulation code for modeling direct evaporative cooling by water spray vaporization is evaluated. A series of parametric explorations have demonstrated that the one-dimenstional model of spray (fluid dynamics and heat and mass transfer) is sufficiently consistent.

This paper sums up how to use CO2-Based DCV with standard 62.1-2004 from a theoretical standpoint. Changes to the way ventilation rates are calculated in the latest version of standard 62.1 require a modification to the way C02 concentration is used in DCV control system . A CO2-DCV approach for single zone systems is discussed in detail.