monitoring

This study presents some results from a monitoring project with night ventilation and earthto- air heat exchanger. Both techniques refer to air-based low-energy cooling. As these technologies are limited to specific boundary conditions (e.g. moderate summer climate, low temperatures during night, or low ground temperatures, respectively), water-based low energy cooling may be preferred in many projects. A comparison of the night-ventilated building with a ground-cooled building shows major differences in both concepts.

Highly efficient thermal insulation of the building envelope demands for layers up to 40 cm thickness.This often causes problems regarding architecture and loss of space, especially in building renovation.An attractive alternative is the recently introduced vacuum insulation panel (VIP) having a 5 to 8 timeslower thermal conductivity than conventional thermal insulation. Aging effects and service life arecrucial aspects of those high performance insulation systems, as gas permeation through theenvelope barrier may drastically reduce the insulation efficiency.

A promising approach to reduce the primary energy demand of office-buildings without violatingthermal comfort is passive cooling by thermo-active building systems (TABS). The presented studyintroduces two low-energy office buildings within the framework of the German programme ENOBwhich are conditioned by TABS mainly supplied by geothermal energy.

Evaluating naturally ventilated buildings for performance is a difficult task, often relying oncomputer simulations and modeling to assess thermal comfort and airflow issues. This paper presents the long and short term monitoring procedures and data devised to determine the overall building performance of a naturally ventilated office building in the United Kingdom.

The study aimed to evaluate the emission of volatile organic compounds from air filters. In the first part of the project, carbonyl compounds were measured by reacting them with 2,4-dinitrophenylhydrazine. HPLC and UV detection were used for the analysis. Laboratory experiments used pieces of used and unused HVAC filters, incubated in test chambers. The used filters used in the experiments were from a filter bank of a large HVAC system in the middle of Berlin, Germany.

Since the beginning of this decade, natural ventilation in office buildings is receiving specific interest. There are two sorts of application. Natural ventilation can be a strategy for indoor air quality control. Besides it can be used as night ventilation during warm or hot periods. In this case the objective is to cool down the thermal mass and improve the thermal summer comfort. The EC JOULE NatVent project wanted to identify the barriers to the application of natural ventilation in office-type buildings in moderate and cold climates and to provide solutions.

One basic goal of the commissioning process is to make sure that the HVA C system is functioning as intended. In particular, it is intended that the HVAC system not only provide adequate ventilation for the building occupants but also achieve adequate pressurization of the occupied spaces to prevent the infiltration of unconditioned air. One technique for evaluating the performance of the HVAC system in these areas is to use continual, multipoint monitoring of carbon dioxide, carbon monoxide, and dew point at selected locations in the building and the HVAC system.