There is no doubt that one of the most important challenges and controversial topics of the current century around the world is the energy issue. In general, there are various methods to conserve energy resources. One of the most common methods is thrift, which can only be achieved through culture. In addition to the issue of saving, the newest idea to save energy is the use of new equipment and systems that are intended for this purpose, and building energy management systems are also from the same category. For example, in many office and commercial buildings, air conditioners and central lighting systems are among the most consumed items. Of course, the use of HVAC system has greatly reduced energy consumption. In order to reduce the costs of the construction industry and make optimal use of technology and the use of communication and computer technology, the performance of building management and automation systems will become more impressive, which will save energy consumption. In fact, the advantage of using new systems , consumption reduction, their simple installation capability on PC computer networks and system control without the need for costly cabling and the use of expensive equipment. Considering the amount of energy consumption and according to daylight and outside temperature, the system is able to choose a cheap consumption method along with saving energy. Considering the optimal temperature of the building based on the type of use it is used for, limits energy consumption to a great extent. This work is done by taking into account the basic information that the employer gives to the system as well as the data that the system has as default, including daily and seasonal changes in design conditions and how to choose equipment. As a result of this process, the exponential consumption of energy and creating high costs for the maintenance of the building is lost.