The Different Kinds of Boiler.......

Although boilers differ in size and whether they stand on the floor, hang on the wall or sit inside a fireplace, probably the most important difference is the way they produce hot water for washing, bathing and showering. Traditional boilers and system boilers heat water in a storage cylinder, typically sited in an airing cupboard. Combination boilers heat water instantaneously (via a special heat exchanger inside the boiler) only when you open a hot tap.

Traditional boilers are the simplest kind, with the fewest components inside. System boilers and combination boilers are more complex and tend to be larger because they always include the pump which circulates water through the radiators, and an expansion vessel to accommodate the increase in volume when it gets hot.

Traditional and system boilers with stored hot water systems are best suited to family homes where hot water demand is usually greatest. The average combination boiler is best suited to single households or couples with modest hot water needs.

A Traditional Boiler

Traditional boilers are available in a wide range of designs and outputs to suit almost any situation. Back boilers save space by sitting inside a fireplace opening and are cost effective like-for-like replacements. However due to recent legislation changes we must always look to replace these boilers with a new high efficiency condensing boiler and it is only in unusual circumstances that a back boiler will be replaced with another back boiler. Wall mounted boilers can be small enough to fit inside a kitchen cupboard and still be powerful enough for the larger property. A traditional or system boiler (one with some system components built into the case) can deliver lashings of hot water to several taps simultaneously. You need space for a cylinder as well as a boiler but modern versions are often surprisingly compact. You also have to anticipate your hot water need but modern controls make it easy to plan around your daily/weekly routine and the new generation of 'high recovery' cylinders are designed to cater for unexpected demand.

A Combination Boiler

A combination boiler heats water instantaneously whenever you open a hot tap, so you don't need space for a storage cylinder. In Summer there's often a delay until it reaches working temperature but the supply is endless. The temperature at the tap is dependent on the temperature of the mains supply and the flow rate. In Winter the delivery of usefully hot water can be very limited - perhaps taking two or three times longer to fill a bath than a traditional system - and simultaneous demand by a shower and, say, a washing machine can result in a trickle at each. The latest models feature high outputs, small stores or pre-heating systems designed to supply more hot water and with minimal delay to save wasting water.