Illustrated booklet for the layman on heating and ventilation in housing which discusses the following: oil heating, wood firing, electrical heating, district heating, heat pumps, solar collectors for domestic hot water, ventilation systems, natural ventilation, mechanical ventilation, push-pull systems, heat exchangers, fans. Appendix discusses measurement of oil-fired system efficiency.
Traces the relationship between ventilation needs and methods and the growth of civilization. Describes the development of ventilation methods and assessment of air quality, especially since the Industrial Revolution. Questions whether currently accepted ventilation criteria are still valid, andsuggests that ventilation is only one of several means of ameliorating the internal environment.
Discusses air quality and the related definitions of ventilation efficiency. Suggests a definition of efficiency for ventilation systems in residential buildings that takes into consideration how ventilation air spreads within a dwelling. Measurements of the efficiency for exhaust, supply and combined systems show that for combined and supply systems the highest efficiency occurs in those parts where the air is supplied.
Examines several ventilation strategies in tight houses for both impact on the total ventilation and effect on the energy balance of the system. Uses the single-zone infiltration model developed at LBL as part of the calculation of total ventilation load. Strategies covered include natural systems such as ventilation stacks as well as mechanical systems such such as air-to-air heat exchangers and exhaust fans with and without heat pumps.
Describes an investigation to see what energy saving can be achieved by the regulation of mechanical ventilation systems in high rise buildings. Measures air leakage in a block of flats, and uses a calculation model to predict the amount of energy lost due to ventilation in various situations. Concludes that the reduction of ventilation has no disadvantageous consequences for the operation of the system, and that the extracted air flow is affected more by incorrect adjustment of extractor vents then by opening windows, regardless of the setting of the ventilator.
The results of a prediction method for calculating ventilation rates in a detached house are compared with experimental measurements described in aprevious paper. The method is capable of giving good agreement for a wide range of ventilation conditions. The need is demonstrated for further work in two important areas - the spatial distribution of background areas and the effect of turbulence.
Many mechanically ventilated buildings are over-ventilated since ventilation rates are based on a fixed number of people (often in excess of the average occupancy) and no allowance is made for infiltration. States that the CO2 concentration in the ventilated space can be related to the ventilation rate per person, and by modulating the fresh air flow to maintain a constant CO2 concentration, a constant ventilation rate per person can be obtained.
TNO Research Institute for Environmental Hygiene have developed a mathematical model (based on an electrical analogue model) for deciding on the best ventilation system (natural v. mechanical) for a building while it is still atthe design stage. This model has been applied to an auction complex situated at Bleiwijk to deduce the best ventilation system for the building. Conclusions are that a natural ventilation system can be realized by placing ventilating devices exclusively in the roof.
Investigations in Denmark show that there are as many as 75 different compounds in indoor air in tight houses including toluene, xylene, and radon. The dust in homes contains a large number of allergically active ingredients, the most important being the dust mite, which occurs in bed clothes.< States that good air quality is therefore difficult to maintain with natural ventilation in new tight houses. If the hygienic demands of this decade increase the need for ventilation, mechanical ventilation seems to stand a good chance.
Gives measurements of the ventilation as well as the temperature efficiency of mechanical supply and exhaust systems (balanced systems). The ventilation efficiency is a measure of the performance of providing air in the occupied zone and is also an indicator of the air quality. The temperature efficiency is a measure of the system's capability of supplying heat in the occupied zone. Monitors ventilation efficiencies by adopting tracer decay techniques and the temperature efficiencies by measuring the stationary temperatures.
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