The valve control example shown on this slide is a high efficiency method of producing residential hot water which is in use in Japan and will likely start to spread to other areas. The block diagram consists of three main sections; the remote unit, the tank unit, and the pump unit. Inside the tank unit, motors are used to control opening and closing of valves as well as opening or closing in varying amounts. A driver array is sufficient for a simple movement of opening and closing, but if inflow control is required; for example to control water temperature by mixing hot and cold water, a stepper motor is used. The LB1948MC is used in many gas hot water supply units in Japan. These units are very similar to heat pumps used in air conditioning systems. The tank unit is equivalent to the indoor unit while the pump unit compares to the air conditioning outdoor unit. Hence white good manufacturers can make both products at the same manufacturing site.