Is it dirty and tiring to do water heating? What's the main reason?

Plumbers are tired, and sometimes they are often exposed to some dirty work, such as dredging sewers. Of course, there are installation work, such as water supply and drainage renovation, heating renovation and so on. Electricians mainly look at what kind of electricians they are, which are generally divided into installation electricians, maintenance electricians, on-duty electricians and weak current electricians. Not tired, but it needs skills. Because electricians are dangerous, such as getting an electric shock.