Danger of backflow is underestimated. Water mains operators rely on a reversing valve in a water meter assembly, but this may not be reliable. Here, health risks and deterioration of drinking water quality in backwaters are known.

The authors describe the economic and technical connections related to the use of thermal solar water heating systems on the Czech market. This includes investment costs, grant titles, operating options, and an estimated lifetime that is roughly twice as high as the economic return.

This Framework of the National Environment Program is the extension of the National Environment Program document. The Framework introduces priority themes to be supported by the National Environment Program over the next three-year period.

Rainwater can be captured and used directly. After simple mechanical cleaning it is suitable for irrigation or flushing toilet, cleaning, car wash or laundry. The basic choice is the pumping of rainwater. The article describes the possibilities.

Revised CSN EN 12897 “Water Supply – Indirectly heated pressure (closed) storage water heaters” applies to indirectly heated pressure container heaters up to a volume of 2000 liters usable in internal water conduits at overpressure from 0.05 MPa to 1.0 MPa. The author draws attention to important provisions of the standard that will be reflected in practice.

The article deals with the issue of water transport by hose lines to fire. It describes pump connections when transporting water according to required parameters at the intervention site. Compares how the hose line is connected and determines the suitability of its use.

The article deals with the economic assessment of energy saving measures as a further continuation of the topic of reconstruction of HVAC systems in apartment buildings. Selection of economical lifespan for selected elements and functional parts with preventive maintenance costs is provided. Finally, an example of the apartment building evaluation is given.

Family houses with the concept of electric heating by means of an electric boiler or electric direct heating system and the preparation of hot water in an electrically heated tank do not meet the requirement for the energy performance of buildings. The authors analyze the magnitude of the conversion factor and other parameters that would meet ENB requirements.

The first article of the series on energetic reconstruction HVAC systems in residential buildings is focused on the preparation of project with minimum necessary information that should be prior to any commencement reconstruction. In current practice this part is significantly neglected.

The paper presents the results of the experimental measurement of cold and hot water flows in the reconstructed pipeline of a residential building. The measured flows are compared to the calculation values according to STN 73 6655, DIN 1988-300 and the values computed by the calculation program. The results can be applied to the optimization of the design of internal water mains as well as the optimization of the design of the hot water preparation plant and its heat source.

Lecturer of Water Management Systems, Stanislav Frolík, Ph.D., briefly summed up what should be taken into account and what decides on a meaningful solution of waste water utilization, including topical issue of rainwater.

No foreign certificate can be used to verify the product for contact with drinking water in the Czech Republic. A foreign protocol on the leach test is sufficient if it is obvious that it is identical to the test specified in the Decree No. 409/2005 Coll.

The author provides a basic overview of technical information on the issue of small solar systems suitable for family houses.

The authors compare the measured data on the production and use of electricity produced by the solar photovoltaic power plant with the total electricity consumption in the production area of the company. The second part of the article is based on considerations about the use of overproduction of electricity for heating and hot water preparation and its economy.

The authors compare the measured data on the production and use of electricity produced by the solar photovoltaic power plant with the total electricity consumption in the production area of the company. The second part of the article is based on considerations about the use of overproduction of electricity for heating and hot water preparation and its economy.

Many countries have developed their national regulations on requirements for one or more types of recycled water, to some extent depending on how these waters are used. Similar recommendations have been made by some international organizations.

What should be hygienists attitude to using recycled water? The approach should be unprejudiced, but critical, based on the precautionary principle. It can not be expected in the future that hygienists will particularly encourage water recycling in the Czech Republic, especially in contact with people and food.

The change of Z1 ČSN 75 5411 was processed mainly due to the incorporation of water meter shaft requirements without the necessity for persons entry (so-called microshaft) into this standard. Current version of ČSN 75 5411 of April 2006 did not mention the water meter shaft without the necessity for entry of persons, and there were doubts as to whether such water meter shafts on the water connections are permissible.