Note: Tempra 36 Plus Requires a 300A minimum electrical service Capacity: 3 Bathrooms (Cool Climate) The Tempra? series has been redesigned completely inside and out - upgraded heavy-duty electronics, a simple single flow sensor design, a hinged cover for easy access, and Advanced Flow Control for the Tempra? Plus. Welcome to the next generation of German quality. 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. Important!Please inspect your delivery before signing for it.Feel free to cut open the box. If you notice any damage that may affect how your unit functions, write a description of the damage on the delivery slip and refuse it.