System Boiler
A system boiler has some of the benefits of a combi, but still needs a separate hot water cylinder.
Average lifetime: 12 years
Space requirement: Small cupboard for the boiler and a larger one for the hot water cylinder.
Combi boiler
A combi boiler provides heat for your radiators and domestic hot water on demand.
Average lifetime: 12 years
Space requirement: Boiler only (a small cupboard).
Regular boiler
Regular boilers (also known as 'conventional' boilers) heat your radiators directly and hot water via a separate cylinder.
Average lifetime: 12 years
Space requirement: Room for cylinder (a full-length cupboard) and tank (usually in the loft or the top of a cupboard).
Micro CHP boiler
A micro combined heat and power (micro-CHP) boiler provides heat just like a standard boiler, and generates electricity at the same time.
Average lifetime: 15 years
Space requirement: Boiler is only slightly larger than an equivalent combi, but you will also need a hot water cylinder.
Solar water heater
Solar water heating systems, or solar thermal systems, use heat from the sun to provide some of your domestic hot water.
Average lifetime: 25 years
Space requirement: Roof space to fit about four square metres of panels, and you'll need a large hot water cylinder.
Air source heat pump
Air source heat pumps absorb heat from the outside air and upgrade it to provide heating and hot water for your home.
Average lifetime: 15 years
Space requirement: Air source heat pumps absorb heat from the outside air and upgrade it to provide heating and hot water for your home.
Wood boiler
Wood-fuelled boilers burn pellets or logs to provide central heating and hot water.
Average lifetime: 20 years
Space requirement: A small room to fit the boiler and to store fuel.
Ground source heat pump
Ground source heat pumps take heat from the ground and upgrade it to provide space heating and hot water.
Average lifetime: 20 years
Space requirement: Space for the pipes (at least several hudred square metres for a horizontal loop, or access for drilling equipment for a borehole) and room for the heat pump itself (about the size of a fridge freezer).