How do condensing boilers work?”
– Condensing boilers work on the principal of recovering as much as possible of the waste heat that is normally rejected into the atmosphere from the flue of standard efficiency (non-condensing) boiler. This is achieved by using an extra-large heat exchanger (or sometimes two heat exchangers) within the boiler. This maximises heat transfer from the burner as well as recovering useful heat that would normally be lost with the flue gases. When in condensing mode the flue gases give up their latent heat that is then recovered by the heat exchanger within the boiler.
