The condensing boilers it's gas boilers more ecological and technologically advanced on the market today. They save gas and reduce emissions into the atmosphere, on the other hand they cost much more than traditional boilers.
As for performance and consumption, with the condensing boilers savings of the order of 15-20% are obtainable for the supply of hot water at 80 ° C (the comparison is with the traditional boilers high efficiency) and 20-30% for the supply of hot water at 60 ° C.
The maximum savings with the condensing boilers is reached when these systems are used in systems that operate at low temperatures (between 30 ° C and 50 ° C) as occurs for example in radiant panel heating systems without radiators (radiant floor, wall, ceiling, baseboard).
The excellent returns of the condensing boilers they depend on the fact that these systems are able to recover the latent heat of condensation of the water vapor present in the exhaust fumes after the combustion of the methane gas.
This heat is equivalent to more or less 11% of the energy released by combustion and instead of being dispersed into the atmosphere through the flue is recovered.
The condensing boilers they cost more than those based on traditional technologies because they must be particularly resistant to corrosion and have a smooth heat exchange surface without fins. In addition, a condensing boiler must be arranged in such a way that the resulting condensate can flow to the neutralizer or to the waste water, which complicates the installation a little.
In the condensing boilers the fumes release the heat to the water that feeds the system, cooling down to return to the liquid state. Their temperature drops to 40 ° C, much lower than the 140-160 ° C of high-efficiency boilers and 200-250 ° C of traditional boilers.
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