Coincidence factor
Heat Interface Units (BG 62/2015) was written by Reginald Brown and published by BSRIA in December 2015. It states: ‘The coincidence factor is formally defined as the design flow rate for downstream domestic hot water outlets divided by the sum of maximum flow rates for individual downstream domestic hot water outlets. In a heat network with HIUs (Heat Interface Units), the coincidence factor is alternatively expressed in terms of the design energy input necessary to achieve the domestic hot water requirements, divided by the sum of maximum energy inputs for individual downstream domestic hot water outlets and used as part of the pipe sizing methodology for the heat network.’
--BSRIA
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