Leakage control of cooling circuits in heat pumps

21.5.2012 | Ing. Marek Bláha, Asociace pro využití tepelných čerpadel  
Article provides detailed information about leakage control of cooling circuits in heat pumps. Author summarizes the legislative basis of this duty and shows, which heat pumps are involved.
4 comments, last 24.05.2012 09:35

The combustion of solid fuels in local heating (1)

21.5.2012 | Ing. Jiří Horák Ph.D., Ing. Petr Kubesa  
The essence of the combustion process is burning fuel. This is a phenomenon that the authors clearly and wittily likened to the relationship of man and woman. At the same time in the article they explain in detail the technical terminology such as calorific value, combustion heat, humidity of wooden fuel, and the efficiency of common and condensing boilers.

Evaluation of calculation of energy use of warm water floor heating according to EN

14.5.2012 | prof. Ing. Dušan Petráš, PhD., Ing. Jozef Bugáň  
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. Warm water floor heating is a progressive way of heating, which decreases operation costs on one hand and creates ideal temperature distribution on the other hand.
Decreasing of energy costs leads to increasing interest in systems with better efficiency and thermal comfort. Utilizing of renewable energy sources along with installation of low temperature heating systems results in decreased primary energy consumption and leads to lower operation costs.
In this article experience with application of the new European standard (EN 1264, 2009) for calculation and design of warm water floor heating is presented. The calculation has been carried out for a reference room in a family house, by means of software with application of floor systems from different manufacturers.
1 comment, 14.05.2012 12:28

The Electricity Consumption Of Households, Its Prediction And Potential Savings Using BACS

7.5.2012 | Miroslav Haluza, Jan Macháček, Vysoké učení technické v Brně, Fakulta elektrotechniky a komunikačních technologií, Ústav elektroenergetiky a Centrum výzkumu a využití obnovitelných zdrojů energie  
At a European level a Directive of the European Parliament and Council 2010/31/EU on the energy performance of buildings (EPBD) has been released in 2010 whereas the main requirement is to reduce energy consumption in buildings (replacing 2002/91/EC). A set of European standards have been issued for its implementation, eg EN 15232 Energy performance of buildings - Impact of automation, control and management of buildings. In the Czech Republic the Directive was implemented by Act No. 406/2000 Coll. energy management and decree 148/2007 on the energy performance of buildings. The current global trend is characterized by promoting energy efficient technologies. The aim of this work is to summarize domestic household consumption, it´s prediction and analysis of potential energy savings by using the wiring system (BACS).

Heat savings - Part 4 - What's heating costing us

30.4.2012 | J.V.Ráž, DiS.  
In the previous article we mentioned the requirements for proper adjustment of heating system after thermal insulation of buildings. This article is to describe some differences between the ways of heating systems regulation, some bad reflection on the functioning of the central heating system and we will address new opportunities.

The results of measurements of selected indicators of the internal environment in the building of the experimental house

30.4.2012 | Ing. Martin Lopušniak, PhD., Ing. Anna Vašková, Technická univerzita SvF Košice  
Concept of energy efficiency buildings provides provable reduction in consumption of energy in compliance with the required user’s comfort. Taking into the account the trend to minimize heat escape and heat loss and increase of the airtight buildings, the installation of controlled ventilation is one of the steps leading to the optimal sanitary requirements and the overall energy efficiency of buildings. Quality indoor environment of energy efficient buildings, as well as the maximum level of comfort in this case is a controlled ventilation system with heat recovery and hot air heating. This article presents partial monitoring in situ measurements of selected parameters of the indoor environment during the operation of the upper and lower distribution system of hot air heating and ventilation in the selected experimental building.

Heat savings - Part 3 - What's heating costing us

23.4.2012 | J.V.Ráž, DiS.  
Thermal energy savings is closely related to the operation modes of heating, elected by the heat customer. The public knows a simple tool "1 ° C = 6% of consumption for heating, but there’s no further information on how to simplify this translates into their own operating costs. This paper builds on the papers "Heat savings - real, alleged, and misleading" and "Heat savings - Part 2 - How to detect (and provide) a return on investment". It offers a simple tool and answers frequently asked questions about operation of heating systems.

"Matrix" of Russian extraction, purchase and sale of natural gas

16.4.2012 | Mgr. Petr Strejček, MBA  
The Russian Federation guarantees one-third of natural gas supply to the European Union. This share has to grow in the medium term to one half. But this is disputed by many critics, mainly because no newly opened bearings and no investment to new projects. What is the real state of the gas production in Russia?

Heat savings - Part 2 - How to detect (and provide) a return on investment

16.4.2012 | J.V.Ráž, DiS.  
The decision to additional thermal insulation of facade begins with a question "what's million-dollar investment will bring us". Many of the available information we find say that it will bring about 50% savings in heating. The heat meter, installed at the inlet of connecting pipe to the heating system should therefore show the half consumption of heat than before, but usually the results are very different - in both directions.

Determination of the effectiveness and degree of utilization of low temperature and condensing boilers

9.4.2012 | doc. Ing. Vladimír Jelínek, CSc.  
The article is focused on methods of verification of declared and year-round efficiency of condensing boiler with heat storage tank, which is based on the knowledge of the temperature of discharged gas and the frequency of outdoor temperature during the heating season.

Common problems in the operation of mechanical services of building: operating rules and equipment fault indication

9.4.2012 | Ing. Jiří Frýba  
Less experienced operating managers in the branch of mechanical services of building can easily get difficulty in identifying the causes of technical problems, which sometimes a common practice brings. The article gives a table of causes and effects of defects and disorders related to cooling and heat sources.

Boilers - Part 2

2.4.2012 | Ing. Marek Baláš, Ph.D., Ing. Martin Lisý, Ph.D., Ing. Jiří Moskalík  
The paper is focused on general description of boilers and their basic classification on the basis of using fuels and main design differences. There are mentioned general descriptions and parameters of particular sorts of boilers. There is put the most emphasis on water tube boilers for combustion of solid fuel and description of grate systems.

Compact Heat Exchanger comparison

26.3.2012 | Ing. Jaroslav Pavlů  
Wide range of air cooled Compact Heat Exchangers is used in Heating, Ventilating, Air-Conditioning and Refrigeration industry (HVAC-R). Compact heat exchangers large air side area is characteristic for air cooled condensing units. Comparison includes 3 types of cross flow heat exchangers. These are expanded copper round tube on aluminium fin, expanded aluminium round tube on aluminium fin and extruded aluminium multiport flat tube heat exchanger with corrugated aluminium fin. Compactness of heat exchanger, pressure losses or its performance is in many cases the decisive parameter for customer choice. An article compares these parameters on various cross flow heat exchanger types in performance ranges 5kW and 60kW. Performance is measured in ambient temperature conditions of 25°C, due to the 40°C of condensing temperature and azeotropic refrigerant R404A, which is common medium for Air Conditioning systems. Selected performances are chosen to compare results on real applications, which is house air-conditioning unit at first case and bigger one for residence air-conditioning system or small industrial cooling.

Examples of boilers revisions according to Decree 276/2007 in older office buildings (III)

26.3.2012 | Ing. Josef Knob, ENTECH-GROUP s.r.o.  
Decree 276/2007 regulates the revisions of boilers with a rated output of 20 kW to 200 kW and over 200 kW and it is to be used for heating of buildings located in these buildings. It is not applied to boilers designed exclusively for heating and hot water in family houses.

How does volume factor influence your invoice for gas taken?

19.3.2012 | Ing. Milan Bechyně  
The amount of volume coefficient depends on elevation of location of gas consumption and the temperature of gas flowing through the gasometer. In this paper we describe the procedure by which you can check that the coefficient of volume on the invoice is correct. The coefficient is one of the factors that affect your cost of gas.
3 comments, last 09.04.2012 00:21

Boilers - Part 1

19.3.2012 | Ing. Marek Baláš, Ph.D., Ing. Martin Lisý, Ph.D., Ing. Jiří Moskalík  
The paper deals with basic separation of fuels and their classification on the basis of various points of view. There are mentioned descriptions of basic characteristics of fuels which are usually determined for standard fuels. Lastly, there are mentioned general parameters of the most widespread fuels and short description of incineration.

Energy from the ground and its use for preheating or precooling of the air

12.3.2012 | doc. Ing. Karel Papež, CSc., Ing. Kristýna Smutná, ČVUT Fakulta stavební Praha, katedra TZB | Český instalatér 6/2011
The article deals with the introduction of underground heat exchanger for preheating and precooling air for buildings. The introduction is devoted to the description of the system and its individual components and parameters that influence the behavior and performance of the system most. The second part presents a simple model, where you can see how each change affects the actual parameters of heat and cold, which can be gotten from the system.
4 comments, last 25.04.2012 01:42

Principles of flue gas from appliances burning gaseous fuels in accordance with the new TPG 941 02

12.3.2012 | doc. Ing. Vladimír Jelínek, CSc.  
This article contains extracts from the new TPG 941 02 Solution flue gas from appliances burning gaseous fuels. Inspections and audits of flues. The rule continues, quotes and refers to the standard CSN 73 4201.

Recommended regular servicing of gas appliances with value-added (II)

5.3.2012 | Ing. Renata Straková, ENTECH GROUP, Ing. Josef Knob, ENTECH-GROUP s.r.o.  
Regular inspection is focused on boilers and smoke flue, its accessories, security and regulation. The article presents the second example of inspection of an old thermal system with modern atmospheric gas boiler in a house with new windows and thermoinsulation of the facade.
4 comments, last 08.03.2012 08:42

The use of waste heat from the geothermal energy system

27.2.2012 | doc. Ing. Ján Takács, PhD., Stavebná fakulta STU Bratislava, Katedra TZB  
The use of GE depends on the predisposition source, namely geothermal boreholes. The use itself is different when using the heat for heating, hot water, heating greenhouses and plastic greenhouses (agricultural), recreation facilities, but also for various technologies. The inclusion of monitoring and control system for an open geothermal energy system is achieved by taking friendly geothermal water and substantially increases the life of the whole work.