Pressure pans are often misused, and the information they provide can mislead the inexperienced. Bruce Manclark of Delta-T Incorporated (Eugene, Oregon) and Jeffrey Siegel, formerly of Ecotope Incorporated (Seattle, Washington), investigate how mistakes are made, and share their research into one strategy for more accurate pan readings.
Modeling of delivery efficiency was performed using three levels of combining measured and default input parameters and compared to measured data from seven manufactured homes. Using values based on all measured data provided modeled efficiency results that were closest to short-term coheat efficiency results. As individual measured parameters were replaced by estimated or default values suggested by the draft version of proposed ASH RAE Standard l 52P, the agreement with measured efficiency results worsened.
A number of systems exist for ventilation of residential buildings. In general, they can be categorized as supply, exhaust, or balanced ventilation systems. Subcategories include integration into central air distribution ducts, or single- or multi-point air distribution. This effort focused on establishing a design methodology for centrally integrated supply ventilation systems using an outside air duct to the return side of a central air distribution fan.
Describes the development of the Swedish duct tightness guidelines, the "AMA system". The latest version, due in 1998, aims to increase tightness requirements once again by introducing a tightness class D as the standard requirement for larger spiroduct systems. The concern about an increasing part of the Swedish population becoming allergic and asthmatic led to the Swedish Parliament introducing compulsory inspections of ventilation systems in 1990.
This paper gives an overview of duct leakage issues in Europe. A literature review indicates alack of ductwork air tightness measurement data in the member states. However, based on afew papers and above all on a field study on 22 duct systems in France, we conclude that theventilation and energy use implications of leaky ducts are large and merit furtherexamination. To this end, we have started the SAVE-DUCT project (1997-1998) aiming atstudying the potential implications of a tight air duct policy at the European level.