Quench Water Recirculation Pump
The function of the recirculation pump is to ensure that water is always available as close to the consumption point as possible, in order to reduce water wastage and to maximize profitability. Circulator pumps as used in hydronic systems are usually electrically powered centrifugal pumps.A circulating pump works by pumping or circulating liquids, gases or slurries in a loop or closed circuit. Their most common application is circulating water in a hydronic cooling or heating system. Since the materials that they pump move around in closed circuits, they do not expend lot of energy.
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(Source: http://www.schuf.com/products/pump-recirculation-valve/78ps)
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(Source: http://www.discovercabrillo.com/plumbing-info/hot-water-recirculating-pump/)
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