Question from Brian Warburton, via email:
When are boiler salesmen going to be realistic in their statements regarding boiler efficiency?
We are regularly quoted figures of a new boiler giving 98% efficiency, this is a ridiculous figure. It may possibly be achieved in a laboratory, but not in the real world.
A increase of 10% on the average old boiler installed in a household would be a big achievement, any more I believe would be fictitious. Who do they think they are kidding?
Answer from Martyn Bridges, director of marketing and technical support at Worcester, Bosch Group:
The SEDBUK scheme, (Seasonal Efficiency of Domestic Boilers in the UK) was introduced for this amongst other reasons. The boiler efficiency figures to which the appliance has been approved can be quoted in different ways, both part load and full load and in either net or gross efficiency.
To avoid some of this confusion SEDBUK was created with an aim of amalgamating the laboratory achieved efficiency figures and adding or subtracting a factor dependant on boiler type, which would then result in an efficiency figure that would be comparable with other boiler types and makes.
Therefore to get a more realistic likely efficiency figure reference should be made to the SEDBUK database whereupon all boilers will be listed, both new and old and a comparison of efficiency made.