Demand controlled ventilation (DCV) systems : performances of infrared detection

For energy savings, DCV systems are more and more used in ventilation systems. In France, in nonresidential buildings, these systems are generally controlled by either a CO2 sensor, or an opticalmovement detection (infrared). The part of the study we present here was to determine laboratorytests methods to assess the performances of optical sensors for ventilation application. The pointwas to characterise them by checking their detection in front of some determined movements orevents.

Demand controlled residential hybrid ventilation

A Demand Controlled Hybrid Ventilation System is a two-mode system using natural forces as long as possible and electric fans only if necessary. Sensor technologies are used to establish the exact required airflow for indoor air quality and thermal comfort to a minimal energy demand. A large part of the Dutch dwellings are foreseen with a ventilation system consisting of natural supply with mechanical exhaust. Fan power for these systems typically is 30 - 40 W (Specific Fan Power 0.7 - 1.0 kW/(m3/s)). Small improvements lead to a laboratory reference of 21 W.

Demand control ventilation systems : performances of CO2 detection

In France, in non residential buildings, these systems are generally controlled by either a CO2 sensor or optical movement detection (infrared).The part of the study we present here was to determine :- laboratory tests methods to assess the performances of CO2 sensors for ventilation application.- the working performances of these sensors, and particularly the long term stability in a meeting room.- a methodology to assess the performances of CO2 DCV system in French technical agreementThe main results of this study are :- it is easy to characterize (to calibrate) the sensors- the long term

Building envelope, duct leakage and HVAC system performance in HUD-code manufactured homes

Between 200,000 to 300,000 manufactured homes are built to the US Department of Housing and Urban Development’s Manufactured Home Construction and Safety Standards (MHCSS) in the US each year. This paper compares building envelope, duct leakage and HVAC s

Accurate performance testing of residential heat recovery units

The Norwegian Building Research Institute (NBI) has completed a study of the performance of balanced residential ventilation systems with heat recovery (HRVs) in Norway. The study involved both a national questionnaire survey and thorough laboratory tests of 10 HRVs on the market. The overall conclusion is that balanced ventilation with heat recovery provides very good air quality, and has a payback time of 4~6 years for the most profitable systems despite Norways cheap hydropower (0.09 /kWh in 2002).

A first study of natural and hybrid ventilation systems in the urban environment

An experimental campaign was organized during the summer period 2002 in Athens, in the framework of the European RESHYVENT Project. The main purpose was to indicate the impact of the urban environment on the natural and hybrid ventilation air flow process in urban canyons. Field and indoor experimental procedures were carried out in two urban canyons, presenting different geometric and urban features. The experiments were organized for more than three consecutive days within three different periods in summer and on a 24-hour basis.

Mold and health issues

Over the past decade, there has been extreme media attention to issues about mold and allegedlyadverse effects. Unfortunately, misinformation about mold and health effects abounds and oftenthe public is led to believe that exposure to mold is a dangerous event. This paper presentscommon points of misinformation about mold and health. Scientific documentation to refute themisinformation is presented.