Mathematical description of a linear dynamic system can be obtained in various ways. Theoretical models are desirable when basic physical laws of nature are known that describes the relationship between input and output signals, mostly in terms of differential equations. If this is not case, approximate dynamic characterization may be received from the statistical analysis of experimental data. The paper describes techniques used in building thermal simulations, with particular focus on state-space models. If excited by real meteorological conditions, momentaneous temperature variations in an enclosure could be computed that are prerequisites for analysis of long-term heating loads, particularly if the model is exploited as a part of the advanced control system.

This paper deals with the issue of comparing simulations for steady and unsteady thermal state at the massive structures. In this paper, computer simulations are compared with real measurements and measurements of climatic data. The evaluation showed that the steady-state temperature can be comparing with real model used after the end of the accumulation phase. It is evident that the requirements for the temperature factor of the internal surface of the solid structures, set by legislation, are a safe assumption.

It is generally recommended that the wood for quality burning should not have more than 20% by weight of so-called energy moisture. The described method allows a unique determination of moisture content of firewood at home.

The paper describes the management of district heating systems with circulating pumps with variable and controlled speed. It is shown that this control method is compared to systems with circulating pumps with fixed speed very advantageous, by substantially reducing power consumption to drive the pumps.

Evaluated the effectiveness of austerity measures must take into account both external and internal temperature of the object and the value of the average heat gain at which heat consumption was measured. Article analyzes the individual components, and presents the average values.

The article is research on the thermal properties of various construction types of thermal drillings. It focuses on the impact of their installation on their efficacy, duration and cost and to their safety for underground water and water-related ecosystems.

This article describes the problematic calculation of local heat flux of floor heating system in accordance to floor structure. Calculation methodology is based on ČSN EN 1264 standard and calculation is applied to three the most frequently used floor constructions.

This paper describes the basic concepts of pumping technology - characteristics of the pump, and resistive characteristics of system, operating point, and deals with the result effect of the series of the circulator in serial and parallel connection.

Relatively same heat savings can be achieved with thermal comfort by regulation, or without thermal comfort by switching off the radiators. It depends on how the heating is operated and how heat gains are used in the building. The article contains a simplified example that relations between real and purported savings of heat explains.

Meaningfulness and financial benefits of the hydraulic system of hot water and heating control are known in the general public. Less well known is need to care for such a controlled system and the possible need to streamline the already regulated system.

The article presents the current state of the issue of flat hybrid photovoltaic-thermal (FVT) collectors, focused on the differences between the basic types of collectors, their advantages and disadvantages. There is also presented an overview of the current global manufacturers. The article aims to highlight the problems but also the opportunities associated with different types of the hybrid FVT collectors.

The heating period 2011/2012 in Prague based on the observation of Prague-Karlov station was 213 days, a little shorter, and with an average temperature of 5,4 ° C, slightly warmer than the long-term average. Year 2012 is leap-year. The basic characteristic is slightly different. Basic characteristic of heat demand for heating is 2 907 D ° (19) degree days, heat demand is much lower than the long-term average of 3 224 D ° (19). It's the second lowest number of degree days of the heating period in the last decade.

Can additionally insulated prefab-panel buildings meet the low-energy standard, or even overcome? The article contains a detailed analysis of the specific parameters of the building and heating system before and after additional thermal insulation of building, supplemented by the results of measuring the actual heat consumption in the period 2010-2011, with output data transferred to the appropriate temperature normal year.

Energy audit in the Czech Republic has twenty years history. The first decade was a period of searching, others ten years were period of legal obligations. The author is one of our first energy auditors. Features personal experience on the development of the methodology, legislation and practical application.

Currently the thermography is commonly used for diagnosis of the building envelope quality. Major purpose is the control of construction details, thermal bridge analysis. Thermography can be used for determining the heat transfer coefficient of the building envelope. Though this method of determining heat transfer coefficient is limited and results may not always be exact. It can be caused by variability of boundary conditions and inhomogeneity of building structure. This article describes the methodology for determination of heat transfer coefficient based on thermographic measuring.

At present, it is not easy to find the optimum variant of the energy used for heating, which would be suitable for all types of houses. Economic evaluation of basic options which are offered should be enough for the choice of method of heating. The article gives an example of the selection of appropriate options for heating and hot water of selected house by comparing the technical, economic and geographical possibilities of nine basic and commonly used variants in the Czech Republic.

Temperature effects on soil are unexplored and calculations are simplified. This paper deals with the impact of using different soil properties for numerical determination linear thermal transmittance of building foundations. It describes how the numerical calculation react on these soil properties. The analysis was made for real details of foundations and was used to create simple chart for the idea about calculation sensitivity.

Nowadays there is emphasis on energy savings and utilization of renewable energy sources. Therefore, proper selection and design of the heating / cooling system, which should be also able to provide favourable condition of the thermal environment – thermal comfort, is very important.In this article construction systems, compositions and possible solutions of low temperature floor heating / high temperature ceiling cooling are presented.

Determination of the energy balance of required building is necessary in energy evaluation, energy audit and energy performance certification of buildings. Key values are heat gains and losses. They are initial for determination of the energy demand and consumption. Calculation of the energy performance should be done in accordance to ČSN EN ISO 13790 standard. This article describes the problematic calculation of glazing solar gains. In the end is enumeration of different methods (current and older) during the heating season.

This article is focused on plan optimization issues of preventive maintenance based on risk assessment. The aim is to propose a cohesive system layout which involves the maintenance optimisation as a whole and achieve better results compare to simple applying the individual methods. This system is divided into five fundamental phases which are consequently following one after another and guarantee the order and structure of the process. Every phase consist of individual sections which thoroughly describe particular execution and procedures. The proposed system should help readers to obtain sufficient information in order to understand the different parts of the system and enable them to make their own opinion on synergy of systematic methodology which deals with optimization of maintenance. All these aspects are very important in practice due to the complexity of most ventilation, heating and air conditioning systems.