Combination (combi) boilers deliver both central heating and instantaneous hot water without the need for a hot water cylinder. Modern combi boilers can now meet the demands of more than one bathroom.

System boilers, traditionally fitted with an unvented hot water cylinder, provide increased hot water capacity. The pump and controls are within the casing, making it a simple, space-saving solution.

Regular boilers, also known as conventional boilers or heat only, are fitted in many UK homes. They offer a straightforward replacement solution, though they typically require loft space for a feed and expansion tank.