Why are many HVAC companies called mechanical and electrical engineering companies? Why

In fact, from the perspective of industry division, the scope of electromechanical is larger than that of HVAC, and the origin of HVAC is not as big as electromechanical. This is why almost every province has electromechanical schools but no HVAC. Generally speaking, electromechanical companies have a wide scope, and their business includes HVAC and other electromechanical products. In order to satisfy customers and traditional conventions, many air conditioning companies just use the name of electromechanical.