Administration tel.: 0191 492 1700
DH2 1AB Birtley Durham
Current market position
Investments Rettig Heating Group are among the largest in the history of Polish-Finnish, which places our company among the most important foreign investors in Poland.
Currently Rettig Heating Group is the largest manufacturer of radiators in Europe. In total, the factories in Finland, Poland, Germany, Belgium, France, Sweden, China production reaches 9 million units.
Purmo brand is very popular among professionals - installers and designers. As many as 88 per cent. designers surveyed and 76 percent. installers declared cooperation with Rettig Heating. And 56 per cent. designers and 35 percent. installers usually uses in working with Purmo radiators. Research shows that professionals choose these heaters primarily due to the well-known brand, a wide range of products and high quality. Very often the customer or investor simply wishes to mount radiators Purmo.
Rettig Heating Sp. z oo, a producer of radiators PURMO has all the certificates and approvals allowing its products to the trade and use in construction. The documentation includes Hygienic certificate PZH and Declarations of Compliance Standard.
In addition, we also provide certificates of compliance with ISO 9001.
The choice of radiators
The radiator is one of the most important elements of central heating installation, because it participates directly in the transfer of heat into the room. Hence the need to the proper selection, ensuring the maintenance of a suitable temperature in the room that will be warmed.
The offer Purmo there are many types of heaters, which differ in purpose, structure, dimensions, shape, color, and sometimes every customer will certainly find the radiator corresponds most to him. Selection of the most appropriate heater for visual reasons, must always be based on a certain size, which is due to the essential function of the radiator is the most important and at the same time is not always well understood. It is the heat output of the heater in watts [W] for the various supply and return temperature of the heating medium and the temperature in the room where the heater is mounted. The heater must be selected so that the heat output is higher or at least equal to the heat demand in the room concerned (often also used to determine the heat losses of the room). The size of the heat loss is related to the characteristics of the building and its location and must be calculated by the designer. These calculations are attached to most projects finished houses, and in individual projects often do not occur.
A common mistake made when choosing the radiators is to define their power benchmarking on the basis of area or volume space. This method is subject to considerable error because the rate of heat demand with respect to the surface can vary from 40 to even 200 W / m² because it depends on many factors that must always be taken into consideration. To enable the correct choice of radiators give some basic factors that we need to know in determining the heat loss of premises and thus the size of the radiators:
- Outside temperature. Depending on the location of the building on Polish territory is determined by climatic zone, for which the calculation is assumed to be outdoor air temperature. It ranges from -16 ° C at the sea to -24 ° C in the mountains. The lower computational outdoor temperature, heat loss, with the same building will be higher.
- Building location and wind conditions. In buildings standing on the open space and in windy regions, the demand for heat is higher than for the same building standing in a dense urban area or in a sheltered by trees.
- Thermal protection systems - heat transfer coefficient of the walls, ceiling and floor. Well insulated buildings with low coefficient of heat transfer through the building envelope clearly need less heat to maintain a comfortable temperature.
- Type of windows and glazing type. High-quality windows with low values of the coefficient of heat transfer, allow savings in heating costs. Large glass increases heat loss.
- The number and location relative to the world, the external walls of the room. Heat gains from sunlight affect the possibility of selecting a smaller radiators.
- The internal temperature. The conditioned is the purpose of the room - the required temperature is higher, the more we have to choose a heater.
- The parameters of the heating medium. In most cases, the thermal power given depending on the parameters of the heating medium, ie. Supply and return temperature and the room temperature at 75/65/20 ° C or 70/55/20 ° C. If the installation is working on other parameters than those given in the tables in power or we have other than 20 ° C room temperature, we use the weightings, providing for an appropriate conversion capacity radiator.
Let us also remember that the heater should be mounted on the outside wall, preferably near the window. Then, the cold air flowing through the window is heated by the heater, and already heated flows into the room. This results in a uniform temperature distribution in the room. Another location the heater will need to increase its size by up to 20%. On the thermal efficiency is also affected by whether the heater will be built or covered and in such cases you need to choose the radiators correspondingly greater.
As you can see the case selection of the right size heater is not as simple as it may sometimes seem. To facilitate this, Rettig Heating Sp. z o. o. has developed a special computer program called Purmo SDG for simplified (but not the indicator) selection of brand Purmo radiators in single-family homes. The program can be downloaded from the manufacturer or installed in a very friendly manner on the basis of input data in most of the above to select appropriate heaters.
For single-family homes offer a wide range of radiators, bathroom, decorative, convector, electric or channel .. It should be noted that in areas where there is increased humidity, ie. Bathrooms, saunas, should not be used radiators and decorative. If the plant is distributed in the walls of the building can be used radiators fed from the side.
In the case of the distribution system in the floor heaters may be used with the approach of the bottom. The amount of radiators mounted underneath the window depends on the distance from the floor windowsill - the lower edge of the heater must be at least 10 cm above the floor, the upper edge of at least 10 cm below the sill.