With global fossil fuel energy resources rapidly dwindling, driving up the cost of energy for everyone, fuel suppliers and manufacturers of central heating systems are increasingly looking to new, more energy efficient technologies in an attempt to conserve energy. Also, the increasing body of evidence regarding the impact of human activities on global warming have made it imperative that we try to find ways to cut our consumption of hydrocarbon fuels, such as natural gas. One of the technologies that have sprung from this drive to conserve energy is the modern, high-efficiency condensing boiler.

A condensing boiler is a type of boiler that can be made markedly more energy efficient than a traditional boiler. Most non-condensing boilers waste at least a quarter of their energy, whereas a condensing boiler can be made over 90% efficient. When fuels, such as natural gas, are burned in a boiler, it is inevitable that some of the heat from this reaction is carried up the chimney and away into the atmosphere. This is why it is impossible to make a boiler 100% efficient. However, it is possible to re-use some of the heat that would otherwise be lost to the atmosphere, and it is this principle that underpins the design of the condensing boiler.

The combustion gases that would normally be lost into the atmosphere are usually at a temperature of around 200-250 degrees Celsius. A condensing boiler uses a device known as a secondary heat exchanger to trap this heat and use it to heat the water from the radiators as it returns to the boiler. This means that it requires less energy to heat the next time round, and energy is saved. The excess combustion gases turn to liquid condensation as they cool, hence the name condensing boiler, and drain away through the drainage system rather than escaping into the atmosphere.

Recent UK government legislation has made it mandatory that all new boilers sold in the UK are to be of the high efficiency condensing type. While these new boilers are more expensive than their simpler predecessors, due to the increased number of parts, the higher efficiency ratings mean that most homes would save a substantial amount of money from their energy bill if they replaced their old boiler with a condensing type. For more information about upgrading to one of the new breed of high efficiency central heating boilers, go to the British Gas website.