Cold water enters the water heater from the cold water inlet connection and pushes hot water out through the hot water outlet connection. Thanks to GMO water heater dip tube, it can maximize the hot water delivery. There are two thermostats on the residential electric water heater. The thermostat at the bottom controls the lower heating element, and the top thermostat controls the upper heating element. Generally, only one heating element is active at a time. Because the lower element touch the cold water first, the lower heating element does most of the work, while the upper heating element is used only when the total tank is cold. Double element non-simultaneous operation and double element simultaneous operation are available. The enamel coating tank is able to prevent the water heater tank from corrosion and install an anode rod to help avoid corrosion. The temperature and pressure relief valve is a safety device designed to open if the water heater temperature or pressure of the tank exceeds certain limits. Water heaters capacity should be large enough to provide adequate hot water during the hot water consumption peak.