Typical Boiler Systems

Conventional Boilers

• A conventional boiler has the most simple design. Conventional boilers operate by using gas jets on a cast iron heat exchanger. Water is passed through the exchanger and gets heated. A conventional boiler has simple controls, making them user friendly. This means it has less parts that will break down and need to be replaced, making conventional boilers more durable than other varieties. However, a conventional boiler will consume more energy than other types. Since it takes time to heat water, conventional boilers typically reserve hot water for taps in a copper cylinder.

Combination Boilers

• Combination boilers function in a similar manner to conventional boilers, except they can provide your taps with instant hot water. Rather than store hot water in a cylinder, combination boilers bring in water directly from the main water line. These are smaller and more economical than conventional boilers, good if space is limited in your home. One disadvantage of combination boilers is that you cannot run multiple showers or baths at one time and the flow rate of hot water is lower than other types of boilers.

System Boilers

• A system boiler is also similar in function to a conventional boiler except all of its main components, such as the pump and the expansion vessel, are built into the boiler itself rather than installed remotely. Also known as a sealed system boiler, this type provides both heat and hot water using a storage cylinder that is kept in a cupboard, so no water tanks are required. With this system you can operate more than one hot water tap at a time and expect good flow rate. However, once the hot water in the tank is gone, you will need to wait for more.

Condensing Boilers

• Condensing boilers can be any of the above types of boiler but use technology to maximize fuel efficiency. They work by reusing heat to warm your water that would normally be expelled outside via a conventional boiler. Cooler water that is not used is passed through a secondary heater that is heated by gases that would have normally been expelled. This water is sent back to your radiators and used to heat your home. One disadvantage is that the technology is still not perfect and condensing boilers are prone to breaking down more often than other types.