Water dispenser power saving switch

As the autumn weather gets darker and the temperature gradually drops, many families are turning on the heating switch of their water dispensers , hoping to drink warm drinking water. However, after the water dispenser is opened, the pure water in the heating tank is heated repeatedly for a long time, which is not only harmful to health but also consumes a lot of electricity. Most of the time, we only need the water dispenser to provide hot water for a short period of time. The author added several components to make the water dispenser have a power-saving function without damaging the appearance of the water dispenser. There is a boat-shaped heating switch K on the back of the water dispenser, which has two positions: heating and off. When K is turned on, the power supply is applied to both ends of the electric heating tube RL through the fuse F and the thermostat WK. At the same time, the power supply is stepped down by the resistor R, rectified by the rectifier bridge Q, and filtered by the capacitor C to obtain a DC voltage of 15V, which causes the relay J to operate. K1 is closed. If the heating switch is turned off at this time, the electric heating tube is still in the heating state until the water in the heating tank is heated to the set temperature, the thermostat WK is turned off, the relay J loses power, K1 is turned off, and the circuit exits the self-maintaining state. , no more heating will be done in the future. The relay should be selected with a smaller operating current to prevent excessive power consumption on the resistor R. If you want to further improve the energy-saving effect, you need to make some small modifications to the heating tank of the water dispenser. The insulation measures for most water dispensers are very simple. They only use two pieces of preformed foam plastic to surround the heating tank, so the heat dissipates quickly. It is best to use polyurethane material (generally produced by manufacturers of solar water heaters) to foam and fill on-site around the heating tank. This treatment can make there is no gap between the insulation material and the heating tank, reduce air flow, and greatly improve the insulation effect.