Dong Mingzhu's original words: "Using aluminum pipes will be much cheaper, so we are also struggling. To cater to the market, we lower the price, and perhaps more people will buy it. But later we thought for a long time, if we replace it with aluminum pipes, you have to ensure it doesn't break for ten years. If it breaks in two or three years, then the consumer is the victim, and they will have to spend money to replace it. Moreover, the conductivity of aluminum and other properties still have a certain gap compared to copper. So we are also researching the technology of aluminum replacing copper, and after several years of research, we still don’t have 100% confidence that aluminum can replace copper. Therefore, I believe that aluminum should not be allowed. The cost of copper is very high. The other day I saw someone calculate online that if aluminum replaces copper for the entire air conditioning system, the material cost of one air conditioner may differ by 488 yuan."