The main function of Domestic Hot Water recirculation in plumbing systems is to control that there is no unnecessary waste of the domestic water consumed, plus it keeps the water temperature constant along the line.
Recirculation creates a loop from the hot water supply point (typically a storage tank) to the bathroom fixtures (taps, showers, etc.) and vice versa. Thus, when hot water taps are opened, it will arrive quickly, avoiding wastes. Typically managed by a timetable time slots, it should be activated at those times when there has been no withdrawal for many hours and therefore the water inside the pipes has cooled. It is usually activated early in the morning before people wake up and in the evening before people return from work, so that when the tap is turned on, the water is already warm and usable.
This avoids wasting cold water (contained in the pipes) while waiting for hot water to arrive from the storage tank. It would also be a waste not to have a timer associated with the recirculation, in fact in this case the recirculation circulator would always be switched on with a consequent increase in electricity consumption.
Recirculation can be inserted either in the storage tank or directly on the AFS inlet of the thermostatic mixer, the choice depending on various factors (availability of connections on the storage tank, available space):
La principale funzione del ricircolo dell’Acqua Calda Sanitaria negli impianti idraulici è quella di controllare che non vi siano sprechi inutili dell'acqua sanitaria consumata, in più consente di mantenere costante la temperatura dell'acqua lungo la linea.
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