Combi Boilers

Combi Boilers are smart enough to work without the need of a hot water cylinder; this is because they produce the hot water for the taps and the heating on demand, so no water is stored for later use. Most boilers sold today are Combination Boilers. There are four Vaillant models within this category and all have the highest efficiency rating:

System Boilers

System Boilers are designed to operate within a sealed, pressurized system and also feature a hot water storage tank, but they don’t need an additional expansion tank.

They are usually best suited for larger proprieties, but because many of the controls and functions are integral to the boiler itself, they save on space and installation costs. There is one Vaillant model in this category:

Open Vent Boilers

Open Vent Boilers are also known as Heat Only boilers and do just that; provide just hot water for the central heating system. Within the system are loft tanks and a cold water storage tank provides the water feed, so it’s a system which because of its design, takes up more space. But it’s very efficient as a heat provider for the heating system. Vaillant has four models in this category: