Comparative performance tests of a domestic storage hot water system with a range of cylinder heat exchangers

Abstract

Domestic hot water is commonly supplied from a storage cylinder heated by water circulated from the central heating boiler. The efficiency of hot water production in such systems is dependent on boiler losses, circulation losses, storage losses and losses from the secondary system of distribution pipework to the draw off points. The present work examines the effect of the size of the cylinder heat exchanger on system performance and considers other aspects of system design which affect overall efficiency. A range of cylinder heat exchangers is tested using three boiler designs with ‘compressed’ draw-off schedules. An optimum heat exchanger surface area has been found for the sizes of boiler employed. An energy balance shows the distribution of energy losses from the system.

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References

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