Modern Condensing boilers, the rudimentary truth
Modern Condensing boilers, the rudimentary truth
A condensing boiler is a high efficiency forward-looking boiler that contains an extra heat exchanger so that the red-hot waste gases transfer a large proportion of their energy to start to heat the mains water to be heated. When processing at high efficiency, the water gas created in the combustion action condenses back into a liquid liberating the latent heat of vaporisation.
A consequence results in this liquid, known as condensate, typically acidic, should be piped away to a drain or soak away. The boiler will be mounted on a wall and the exhaust fumes will go through the flue. Hot water is first delivered by a small-scale recepticle tank to facilitate rapid hot water availability.
Can you advise on the right boiler size?
You should bear in mind that in the past central heating engineers frequently put in boilers that had a higher output than strictly necessary.. Whilst this ensured that there was little chance of the boiler failing to meet the need for heat, even in the most arctic of conditions, it also meant that they were only employing a part of their heat generation capabilities, and so working under their projected optimal efficiency. If you have insulated your household since the previous boiler was put in, it could well be that you will be recommended to install a smaller boiler than before.
Before you buy a freshly boiler we recommend you get information from a CORGI registered installer.
Do the radiators need to be oversized with a condensing boiler?
The main driver for smaller fuel consumption from a condensing boiler results from having a bigger heat exchanger. Bigger radiators would allow lower return temperatures, and so result in even better energy performance, but the extra benefit has not been viewed as cost effective, holding in mind that the system is is only using a small part of its total capacity for the main heating months. That probably remains true, though the reduced heating requirement for new build may well mean that householders would now endure over-sized radiators more willingly.
These effects were studied during the SEDBUK initiative, during which it was considered whether condensing boilers required to be handled differently from others. The outcome was that no new recommendations were demanded, and the test results forthe condensing and the existing boilers employ the same SEDBUK calculation.