Gas-fired water heater is not required to open the valve?

Usually at home, which is the peak of the house with hot water to keep the water heater power-on state, Gas Valves open state, as long as the barrier water heater, it will not start, and use it every time, you only need to open the hot water tap on the line, the water heater It starts automatically. No one at home, it is recommended to turn off the power to the water heater, there is no electricity, the water heater inside the Gas Control Valve is not open, there is no danger of leakage. Nobody at home for a long time, such as travel, long holiday, close the valve, turn off the power, do not unplug the plug, you can let go of the remaining water inside the water heater, specifically refer to the manual operation, there must be this, this is the case, the plug has You can unplug