Issue 1/2004

The article represents an integral information about the course and character of the heating season 2002/2003 in Prague. From the climatic quantities measured at Prague-Karlov observatory the values of quantities were determined necessary for the calculation of heat demand for heating and climatological data giving a clearer picture of weather character of this period in the whole Czech republic.

The contribution deals with problems of water control valves dimensioning for capacity control of ventilation heat exchangers. The attention is paid to the choice of the right valve characteristic type and to the expression of all important valve and heat exchanger and water distribution network parameters influence on the valve size. The attention is also paid to determination of the limit air heating up under observation of stable course of control process. The procedure is documented by worked out example of water air pre-heater of air conditioning equipment.

The article represents a very erudite contribution to long-running discussion concerning the content of the term “Air conditioning” very frequently used mainly in commercial practice. The author proceeds on the base of historical sources relevant to air conditioning engineering and ventilation engineering in general and by logical procedure he comes to the validity specification of this term for the differently configured ventilation systems. The importance of the article lies especially in contributing to unification of terminology the up to now disunity of which is used to be the reason of different misunderstandings under design, commercial and operation practice.

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In this article some less common solutions of heat pump utilisation for heating and warm service water preparation are rounded up that were elaborated at the Institute of environment engineering from 1999 to 2002. The operation knowledge is indicated for the majority of the complemented examples.

The article deals with the use of heat insulation and reflex foils on peripheral wall behind the radiator. It presents the experimentally verified conclusions and recommendations concerning the use of aluminium foil behind the radiator.

The contribution deals with possible utilisation of refrigerating equipment waste heat for heating, ventilation and warm service water preparation. The actual example of the new meat production factory design exemplifies the benefit of waste heat utilisation by its transformation by means of heat pump to the temperature level of ca 60 oC and connection to energy sources. The new designs conception has been evaluated economically.

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The concentration of light ions in atmosphere was measured at twenty-one workplaces at different floors of six air conditioned buildings. The measuring was carried out due to the health difficulties typical for the syndrome of sick buildings (SBS – Sick Building Syndrome). The found out values were compared with values found out in the building with natural ventilation and in the outside atmosphere near the measured buildings. The difference between these values was statistically important. The question arises if this reality is not responsible at least partially for the sick building syndrome.

The article deals with the state of clean rooms standardisation with orientation on their validation. Further it describes the individual tests that have to be carried out before and in the course of putting the clean rooms into operation. Based on the experience of clean rooms validation the article mentions the faults made in the course of clean rooms solution both at the designing and implementing parts and their impact on the clean rooms quality.

The author brings an important information about topical problem at the field of atmosphere protection relevant to small stationary sources of contamination. New legislative duties of operators of small boilers of nominal heat output lower than 200 kW are clearly described. The article brings information about the waste gases of these boilers measuring, the checking of their technical condition, the combustion efficiency measuring, the waste gases paths checking and further relevancy. The author presents practical experience of his own measuring and further problems brought by new duties.