SEDBUK
SEDBUK is the Seasonal Efficiency of Domestic Boilers in the UK, the methodology for determining boiler efficiency defined in the Standard Assessment Procedure, Appendix D.
It was introduced to provide a standardised way of comparing different models, helping homeowners and professionals choose the most efficient options. The system calculates efficiency based on various performance factors, including heat loss, fuel type, and operational conditions.
Originally, SEDBUK ratings were given as letter grades, ranging from A for the most efficient boilers to G for the least efficient. However, this was later replaced by a percentage-based system to provide a more precise efficiency measurement. A higher percentage indicates better energy performance, meaning less wasted fuel and lower energy bills.
Understanding these ratings can help in assessing whether an existing boiler should be upgraded to a more efficient model.
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