How can gas boilers achieve 110 % efficiency?
At present, almost 100 % of fuel conversion to useful energy can be achieved with condensing technology alone. The advantage of condensing boilers is that they also use the heat of the water vapour produced during combustion for heating. The energy fuels have different water contents and are converted to steam during the combustion process. In an average residential house with a conventional boiler, about 3000 litres of water passes through the chimney as water vapour per year. If you wanted to heat that amount to vaporisation, you would need quite a bit of energy. It is this energy that can be used as useful heating energy in the reverse process by condensation. If we harness the energy of the water vapour, we climb over the magic 100 % energy efficiency, thanks to the agreement of manufacturers in the past, when this was not yet technically possible.
How do we achieve maximum efficiency with gas condensing boilers?
If you have chosen gas as your heating source, we recommend a condensing boiler as your first choice. This is especially true if you have chosen underfloor, wall or combined heating. In order to achieve maximum efficiency, it is important to heat the water in the heating system to as low a temperature as possible, which still covers the heat losses of the building and ensures the desired room temperature. If the water in the system (e.g. underfloor heating) is less than 40 ˚C, we can be sure that the flue gases in the boiler have cooled down to the point where the water vapour condenses successfully. The efficiency of a gas boiler is up to 110 %, while an oil condensing boiler achieves a few percent less due to the lower moisture content of the oil.
For which buildings are gas condensing boilers the perfect solution and in which ones will they not deliver optimal results?
The renovation of an existing building requires consideration. In particular, we advise against installing a condensing boiler in buildings that do not have a well-insulated façade and good quality windows, resulting in high temperature losses. Heating such a building will require a higher incoming heating water temperature than the optimum 40 ˚C, which will be most pronounced during periods of low temperatures. While the condensing boiler will provide sufficient heat required by such a system, it will not operate at maximum efficiency. Exceptions are buildings with good thermal insulation and slightly oversized radiators. In this case, due to the size of the heating elements (radiators), the building can still be heated at lower temperatures without losing the advantage,
provided by condensing technology.
