There are many different kinds of HVAC units. There is the air conditioner which comes in three basic different forms. First, there is the central air conditioner which is typically outside of the house and workers to evenly cool the entire house. Central air conditioners are very popular and very expensive to get installed. The next air conditioner is the window air conditioner. The window air conditioner is a small air conditioner that is installed in your window. These types of air conditioners are relatively cheap and can be installed without the help of an HVAC technician. The biggest downfall with a window air container is that it only can cool one room at a time and it can also raise your electric bill pretty quickly as well. Lastly there is the split air conditioner system which is broken into two parts, one of which is outside the building, and the other is inside the building oolong the room. This type of air conditioner cools usually only one room like the window air conditioner, but it is much more powerful and effective. I will also mention in this article two different types of furnaces. First there is the normal electric furnace which, as the name implies, uses electric to heat registers that are mounted on the walls of the house. Oil and gas furnaces run similarly. Lastly there is the portable space heater which is a small heater that is best used to heat your feet under a desk or to heat a small room like a bathroom. The portable space heater is getting less popular since it is pretty ineffective.