Question

Which type of boiler is most efficient?

Answer 1

condensing boilers

Modern boilers are more efficient for several reasons, but their main advantage is that they are all condensing boilers. A condensing boiler has a larger heat exchanger, so it recovers more heat, sends cooler gases up the flue and is more efficient.

Answer 2

Answer:

For larger homes with multiple bathrooms, particularly with showers in use at the same time, a system boiler with a large hot water cylinder is nearly always a better option. Bigger combi boilers have been developed to provide lots of hot water, but they can make the heating system less efficient.