There are several types of air conditioning systems available today. They range from the largest central plant systems down to standalone room air conditioning units. Each of these systems has their own advantages and disadvantages. Below, we will look at the good and the bad when using room air conditioners:
The most immediate benefit is cost. These are by far the cheapest units to install and run. This is why it is the most popular choice for homes, small office rooms and offices. It would even work as a server room air conditioner for a small data center or as a backup. Another benefit is control. Unlike some of the larger units, this allows room level control of the temperature. Which is why when there are different cooling requirements from room to room, room air conditioners are the only choice.
Maintenance is the biggest disadvantage. Each unit has several components that need regular maintenance. Multiply that by the number of units in an office or home and the maintenance load can become significant. There are other issues like fan noise and the noise generated by the outdoor units. There are also limits to the cooling output of these, with high heat loads (like outdoor cooling) requiring multiple units. Lastly, they recirculate the air in the room, providing no fresh air, although some models come with fresh air input.