English

A robust Fault Detection and Diagnosis (FDD) strategy for centrifugal chillers is presented in this paper along with its validation using both laboratory data from ASHRAE RP-1043 and field data from a centrifugal chiller in a real building.

Five papers dealing with ventilation, comfort, indoor relative humidity, filtration and air cleaning constitute this file on "Indoor Air Quality". All the authors have in mind to obtain a good indoor air quality coupled with energy saving .

This paper highlights some of the results of ECA report n° 23 that aimed at providing information and advice on strategies for achieving a good balance between good IAQ and the rational use of energy in buildings. The major strategies are : control of p

A new mode of ventilation , the intelligent stratum ventilation, where the outlets are located at the side walls at the breathing zone level, is presented in that paper. A CFD study is undertaken and a practical example illustrates this new concept.The results are promising.

The existing analytical models for the purging of excess buoyancy by displacement and mixing ventilation have been extended to allow the authors the simulation of natural ventilation with time-varying vent areas.The resulting analytic solutions have been applied to a typical office to obtain predictions. Those predictions have then been compared to those based on a constant vent area model .

For the removal of volatile organic compounds (VOCs), zeolites can be used. This paper deals with the removal performance of toluene in gas phase. A filtration system using zeolite at different ozone concentrations and moisture conditions has been investigated. The experimental results are presented.

The tests were made in a empty experimental surgical room for pre clinical animal research. The measurements were made with 3 filters efficiency : 65 %, 85 % and HEPA filter, according to ASHRAE conditions. The particle samples were taken at the upstream of the air conditioning system and on the operating table. Data collection were done the same day. The results show that the particle concentration is dominated by the smaller particles, so the use of high efficiency filtration is the best alternative.

Activated carbon filters have been installed within the air handling unit of an HVAC system feeding 100% fresh air to an office building. The filters efficiency against ozone (O3) and nitrogen oxides (NO2 and NO) as function of time and outdoor air parameters (temperature, relative humidity) has been measured continuously over a one-year period. The results show that the filters efficiency is high (generally between 70 to 90 %) and varies along time with temperature and relative humidity of air.

The purpose of this study was to investigate the sensory emission load from an alternative ventiltion bag filter with activated charcoal lining and to compare it with a used bag filter. The two types of filter have been used during three months in the same building, under the same conditions. Samples have been sent to a controlled laboratory environmentfor chemical measurements. The results confirmed that the sensory pollution load of the alternative filter is significantly lower than the commonly used ventilation bag filter.

This study experienced the capability of soil to purify indoor air pollutants. The efficiency of reducing the concentration of VOCs was examined for the soil where plants could be buried. Experiments were performed. The study was performed under limited specific experimental settings. The results indicate that IAQ could be improved by soil material, since the concentration of VOCs was lowered.