Closed system
The Chartered Institute of Procurement & Supply (CIPS) Glossary of procurement terms, defines a closed system as: ‘A system or process that, once started, does not allow new entrants. A framework agreement might have multiple buyers and multiple suppliers, but once set up no additional buyers or suppliers can be added to it.’
Water Treatment for Closed Heating and Cooling Systems (BG 50/2021), second edition, by Dr Pamela Simpson, published by BSRIA in 2021, states: ‘Closed systems are effectively sealed and the water inside the system is not exposed to the atmosphere. They contain a fixed volume of water that recirculates and tends to suffer only negligible water losses in normal operation.’
BG 87/2024, Useful Information Guide, written by Chin Hang “Kay” Lam and published by BSRIA in 2024, defines a closed system as: ‘A hydronic heating or cooling system which is effectively sealed. The water in the system is not exposed to the atmosphere and should suffer no, or only negligible, losses in normally operation.’
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