SEDBUK Efficiency Table

sedbuk-rangeIf you’re looking to buy a boiler these days, there is one thing that you have to consider, it’s efficiency rating.

In days gone by, efficiency ratings were just not an issue. Fuel was plentiful and cheap, and global warming hadn’t yet been recognised as a threat to the world’s survival. Boilers were often only 50% efficient. And in case you are wondering, that means for the fuel you used, only half of the energy was used to heat the water. Half of the energy went up the flue. Not bad maybe in the days when coal fires were still the rage, but things had to change, and quickly.

It was made law in April 2005 that when a new boiler was specified, or installed, it had to be of the high efficiency type. In other words, it had to use as much fuel as possible to actually heat the water.

And planning regulations now insist that wherever practical, or possible (bearing in mind the type of property you have), a boiler which is rated A, or B on the SEDBUK scale, must be used. The exemption may be, for example, a terrace house, or cottage, which can only install a back boiler which by their very design and location, cannot always be high efficiency.

But, for most people, the only choice is between Band A SEDBUK, or Band B SEDBUK. And given that the more efficient your boiler, the less money it costs to run (because its making the very best use of the fuel you’re paying for), then it’s in everyone’s interest to install the highest efficiency model they can.

No-one need get hung up on SEDBUK, which stands for Seasonal Efficiency of Domestic Boilers in the UK, because all the main manufacturers abide by the scheme and each of their boilers are graded accordingly, not only in terms of A, or B, but also their percentage of efficiency.

Take the Greenstar FS 30CDi Regular 90.5% A from Worcester Bosch. This means that is it graded 90.5% efficient and thus is in the A Band. In other words, it uses 90.5% of the fuel in the heating process; only 9.5% is wasted. Compare that to the old 50% to 60% boilers.

The bands in full in the box on the right. They were compiled from test data which saw boilers put in an average house and their operation monitored. From such tests came a table of SEDBUK ratings.

SEDBUK will shortly be replaced by a new European standard.