Allergy & Air on March 9, 2015 38 Comments In the last few years, portable air conditioning units have been growing in popularity. Whether it’s how much money they save you or just that people are tired of having bulky A/C’s awkwardly sticking out of their window, they are becoming the new must-have item for homes across the world. Instead of taking up precious window space, the portable unit has hoses to exhaust warmed air out through the window. The tubes are held into place with adjustable frames. Everything you need to install the unit comes in the box, but you’ll need access to a window in order for the unit to work correctly. When it comes to properly venting your air conditioning units, here are two main types that you should be aware of. Some units only have one hose, while others have two. Let’s take a closer look at the differences between dual hose and single hose air conditioners. What Do the Hoses Do? For a complete understanding of which type of portable A/C unit is best for your home, you should understand the purpose of the hoses. No matter which option you choose, every portable unit must draw air in from one vent and then exhaust it from another part of the machine. The exhaust is sent outside of the home through one hose and air may be drawn into the unit through another. It can also help you to know that any air conditioning system actually makes more heated air than it does cool air. The efficient removal of heated air is absolutely necessary if the room is to be cooled. Single Hose Air Conditioning Units The main difference between the two different options is, of course, that one unit has a single hose and the other has two. The single hose air conditioner pulls warm air from the room, sends it past coils cooled by refrigerant, and then sends heated air and moisture through the hose and out of the house. This does create a negative air pressure situation as air is pushed out of the room. The result is that any cracks around doors and windows will allow hot outside air to leak into the room, and will actually pull that hot air into the home. If the area being cooled is very big, the machine will have to work harder and harder to cool the room. On the other hand, if the area isn’t big, then the one hose system can provide sufficiently cooled air without costing too much. There are a couple of important things to keep in mind here: The single hose air conditioner is meant to be temporary and portable. This means that it is easy to move it to the specific areas of your home that need cooling. For the single hose portable air conditioner to be effective, you need to very carefully determine the BTUs of the machine you’ll be using. If you intend to use the unit in a room with computers or even a mini-fridge, you’ll want to choose a more powerful machine. Dual Hose Air Conditioning Units The other type of portable air conditioning unit is the dual hose unit. This model has a couple of intakes and one outtake hose. Through the intake, air is drawn into the unit where it is cooled and then sent back into the area. The machine heats up through the process and an intake hose pulls air from outside the home to cool the air conditioner down. A second hose sends all of the warmed air outside of the home. With this efficient exchange of air, the dual hose system doesn’t have to work nearly as hard as the single hose option. For larger spaces, the dual hose A/C unit is a better choice. The dual hose machine eliminates the negative air pressure problem, but also costs a bit more. This air conditioner operates more quickly than the other and also requires more electricity. Compare BTU and EER ratings, as well as manufacturing quality to determine which of the models are most appropriate for your setting. The Importance of Good Research When temperatures begin to warm uncomfortably, you may feel tempted to purchase an air conditioning unit as quickly as possible just to get comfortable. You will enjoy better results, however, as you take time to research the different options and compare the benefits and drawbacks of those options. In fact, the best time to make this decision is probably before the red on the thermostat starts to rise. With time to do some research and take measurements, you’ll be able to get the air conditioning system you want in place before there’s any chance of being uncomfortable.