1 Find your approximate ground water temperature on the map.
2 Check the column on the table to see how many fixtures can be supplied at the same time for each model.
3 Use the actual max. flow rate to fine-tune these recommendations.
4 Make sure you have sufficient electrical service for the model.
From the Manufacturer
The Tempra® Plus is the most technologically advanced tankless water heater available on the market today. Advanced Flow Control is exclusive to the Tempra® Plus and ensures a constant temperature output no matter how great the hot water demand is. Advanced Flow Control technology works by automatically adjusting the flow of water to eliminate unpleasant temperature fluctuation. What that means to you is a consistently satisfying experience every time, all the time !