VIABILIDADE DA IMPLEMENTAÇÃO DE UM SISTEMA AUTOMATIZADO DE REDIRECIONAMENTO DE ÁGUA FRIA QUE SERIA DESPERDIÇADA NO BANHO
DOI:
https://doi.org/10.46421/entac.v18i.1248Keywords:
Instantaneous gas heaters, Water storage tank, Cold water, Hot water, Economic feasibilityAbstract
In flats where there are instantaneous gas heaters to heat water there is waste of cold water due to the large lengths of pipes between the water fixtures and the heater. The water in such pipes suffers thermal losses and is wasted while users wait for hot water. This paper analyses the economic feasibility of implementing an automated system that saves such cold water by redirecting it to a potable water tank. Firstly, the amount of water that would be wasted was estimated by analysing plumbing designs. Based on the lengths of pipes between the showerheads and the heaters, it was possible to quantify that, on average, 6.95 litres of water remain in the pipes. In eight flats it was possible to measure wastes by collecting cold water at the beginning of a hot shower. It was observed that 9.28 litres of water are wasted until the water temperature reaches 30°C. The automated system was validated by means of a prototype. It was considered the installation of the system in one or two showerheads per flat. The automated system to save the cold potable water is economically feasible under the conditions adopted.
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