Viết ít nhất 150 từ trong khoảng 20 phút.
The diagram shows how a central heating system works in a house.
Overall, cold water comes into the house and is stored in tanks, and then it is heated by a boiler. The hot water is used to heat the rooms through radiators and is also sent to the taps.
First, cold water comes into the house through a pipe and goes into a water tank in the roof. This tank is used to fill a storage tank. There is also an overflow pipe, which takes away extra water from the tank.
Next, the water goes from the storage tank to the boiler, which uses gas or oil to heat the water. After the water is heated, some of the hot water goes to the taps, so people can use it for washing. The rest of the hot water is pushed by a pump through small tubes to hot water radiators in different rooms of the house. The radiators give heat to the rooms. When the water becomes cold, it goes back to the boiler through the cold water pipe to be heated again, and the process continues.