How a combination boiler can save you money and space

Combination boilers have become popular in today's homes because they can save both money and space. A combination boiler heats water from the cold mains on demand, eliminating the need for a standard hot water storage tank, freeing up to 45-50 cm of floor space.

In many households, boilers account for about half of the energy bill. Replacing an old standard boiler with a new, high-efficiency combination boiler can potentially save hundreds of dollars per year. For example, replacing an old boiler that is less than 70 per cent efficient with a 90 per cent efficient boiler can save an estimated $150 to $500 per year, depending upon the type of residence. Even when an 80 per cent standard boiler is replaced by a modern combination boiler, savings will still accrue.

A combination boiler heats water much like a standard boiler, except that it employs an additional heating circuit. Such a unit directly feeds water from the main water supply to a heat exchanger. A combination boiler can provide a virtually unlimited supply of hot water as long as the boiler is continually fired.

The heat exchanger is a key component in a combination boiler. It enhances the efficiency of the unit by extracting heat from the flue gases. This heat is used to pre-heat the water. When gas or oil combusts, approximately 8 per cent of the fuel's energy normally escapes via the water vapour that is released. A combination boiler employs a second circuit to capture much of the energy that is ordinarily lost with a standard boiler.

Combination boilers can heat water in approximately 40 seconds. However, the absence of a hot water storage tank means that hot water is not always available immediately. So-called "storage combis" address this by storing a modest amount of hot water so that it's available on demand. A knowledgeable contractor can assess your specific needs and make appropriate recommendations.

If a retrofit is required, a professional heating and plumbing contractor may offer a no-obligation estimate that takes into consideration necessary changes in gas, water and venting systems. The costs of installing a new, energy-efficient combination boiler may be higher than the costs of installing a standard system; however, the absence of a tank eliminates some pipework and hastens the installation work. This helps to bring down the installation costs. Long-term energy savings make a combination boiler a cost-effective and environmentally wise choice.