How does the radiator heat up to keep the whole house warm?

Heating is a heating element, and its task is to warm a room, just like boiling water in a kettle. The difference is that the kettle is a closed container relative to water, and the room is not closed relative to air. Think about it, if cold water is injected into the kettle when boiling water, the water will never boil, and all the heat of the fire will be absorbed by the cold water. Similarly, if the heating element heats the indoor air, the outdoor cold air will flow again. Is to put the radiator in the window, doorway and other places where cold air can easily enter the house. When the cold air comes in, it is heated into hot air by the radiator. Hot air rises and forms convection with indoor cold air. Cold air circulates near the heater and is heated into hot air. Hot air circulates in the room, which is very warm. Therefore, the heating system including radiator and electric heater (Shanghai seems to be called Youting) works in the above way, not the so-called heating of objects. As can be seen from the name of the heater, warmth is "qi" PS 1. Heating in the north is to use high-temperature water heated by large boilers to circulate at high speed in the radiators of thousands of households through pipelines. The heating area of the heating boiler is too large, and the heat of the radiator will vary according to the distance from the main pipeline. Near heat is far cool, because water will lose some heat during circulation. Every radiator has a water valve, and many people secretly open the water valve to get hot water. If many people do this, the boiler needs to be constantly filled with water to ensure the water quantity. It wastes water and coal. Later, the heating company came up with a trick to add chemicals to the water. It not only changes the specific heat of water, but also prevents the general public from using the water in the radiator casually. Kill two birds with one stone. The heating medium in the radiator is above 100 degrees, so the heating effect is very good. The room will remain warm for a long time after the heating is stopped. Because the room is full of hot air, it takes a relatively long time to turn most of it into cold air. Most windows in the north are double-decked. The air layer in the middle plays a good role in heat preservation. Therefore, in order to save energy, many heating companies stop heating for a period of time in the middle of the night instead of heating for 24 hours, which is also based on this principle. (Although a little cut corners, I have limited energy. )