Which model of tankless water heater should I purchase?
The best way to size an on-demand water heater for any application is to estimate the peak flow capacity that will need to be supplied by the water heater at any time. For residential use, this will most likely be the maximum number of showers that may be used simultaneously, multiplied by the flow rate of the shower heads. This calculation should only be done by a qualified plumber or contractor. Once this maximum flow rate is calculated, consult the specifications for each heater to determine which model meets your demand. Please consult with your plumber or contractor. NOTE: There is no harm in installing a heater larger than your calculated needs. As the heater only makes hot water as you need it, a larger model will ensure that when relatives or family are visiting, and your peak usage exceeds your calculations, there will be enough hot water.
