In front theme heating liquid and gaseous fuels wrote for heating gas and conventional gas boilers, condensing only hinted. This time I will write more about them.
As can be seen from their name they condensation, which in conventional boilers should be avoided at all costs. Just condensate in these boilers increases their efficiency by 107-111%. 111% is the maximum (theoretical) potential efficiency boilers typically have an efficiency around 107-109%. Very wrong to think and say that this is efficiency (efficiency) in condensing boilers talk about coefficient of efficiency. Before explaining the difference will describe the operating principle of condensing boilers.
How it works condensing boiler?
Upon combustion of the fuel to form water vapor, as in the fuel (gas) containing hydrogen. In contrast to the conventional boiler, wherein in order to avoid condensation flue gases have a temperature of about 150 – 200 ° C, under condensing aims to condensation. Therefore, the flue gases leaving the boiler at a temperature below 55 ° C. Below this temperature the water condensation. When condensation of water vapor to release energy that is the energy that has been consumed for the evaporation, and this energy is called latent heat of evaporation. To obtain condensation and proper operation of condensing boiler heating system is necessary to low temperature (these are underfloor heating systems with convectors and other systems designed for the low-temperature).
What is the difference between conventional and condensing gas boiler?
The most significant difference is that condensing boiler has a large heat exchanger, specially made to work in conditions with separation of condensation.
Because of the lower operating temperature condensing boiler we reduce heat losses from the boiler and less heat lost with the flue gases. Condensing boiler consumes less gas compared with conventional, at the same power.
Higher price than conventional condensing boiler. Need sizing and construction of cryogenic equipment (some boilers is only part of the installation is a low).
It is important to know that the optimal operating modes (they are usually given the data in the catalogs of the manufacturers) are at the input / output heating system: 40/30 ° C condensate and 70/50 ° C (80/60 ° C) for conventional boilers.
And finally to get back to the topic of efficiency and boiler efficiency. Since efficiency is calculated as the quantity of produced energy is split in to the amount invested in conventional gas boilers have an efficiency about 93-94% of a maximum of 100% (the difference between the two is the loss of heat from flue gases and boiler). In condensing boiler already wrote, is used latent heat of evaporation, which increases the heat with a maximum of 11%, it follows that the maximum is 100 + 11 = 111%, but it is not efficiency, but efficiency levels as as has been referred to the upper calorific value of the fuel (added is latent heat of vaporization).