Precision Plumbing
All the hot water used in a house theoretically provides the GPM required for the household when it is all combined. It is unlikely that all the washing machines, faucets, bathtubs, showers and tubs will be used at once. A unit rated at 5 GPM is sufficient for small homes; 7-10 GPM would be adequate for large houses. For those who require more heating power, twin or multiple heaters are available.