Does it bring in fresh air? No, air conditioners do not bring in fresh air from the outside. That's not how they were designed. What actually happens is that your air conditioner uses a fan to draw air into the unit and disperse it through a structure.
In short, the answer is no, air conditioners do not bring in fresh outside air. Rather, it takes the air inside your house and puts it through a heat exchange process. So, how exactly does it work? Generally, air conditioners move unwanted heat out of your home, thus lowering the temperature inside your home.
A dual hose portable AC unit does not put outside air into your house. It takes air from outside, cools the condenser coil, and then exhausts back outside. You'll be fine.
How Whole House Fans Work. Whole house fans pull outdoor air into a home through open windows and exhaust it through vents in the attic and roof. This air circulation, in cubic feet per minute (CFM) provides cooling both in the house and the attic.
If you use portable air conditioners, the number of hoses will dictate whether they're safe to use in smoky conditions. Models with a single hose can pull smoke inside, meaning you should avoid operating them in these environments. If yours is a two-hosed model, check for a secure seal between the window and vent kit.
It's a common belief that window ACs bring fresh air into your home from the outside. We're here to tell you—that's not true. Instead, a window air conditioner normally pulls air into it via a fan, cools and filters it, and then recirculates that air back into the building.
The air conditioner's cooling cycle includes pulling in warm air that is then cooled. As a result of this process, condensation is produced. When moisture builds up in the heater box, it may eventually turn into vapor and get released with the cooled air, so you see white smoke coming from the air conditioner vents.
In short, no. Though in split system air conditioning design, commonly heat pumps, part of your system is located outside your home, it does not take in outside air. Outside air is brought into the system from an intake which is generally located by your furnace but is occasionally its own, separate system.
Whole house fans which are large enough to create a breeze through the house can sometimes produce unintended effects such as noise, heat loss, and house depressurization. This can be improved with more attic vents and window area to replace the exhausted air. You must open windows.
Pros of Continuous Fan
The primary benefit of running your HVAC fan consistently: Air circulation improvements. Running the fan more often means air in your home circulates faster, leading to everything from more even temperature distribution to faster heating or cooling.
A portable room air conditioner operates by drawing warm air from the room into the unit. This air passes through a filter, which cleans it by removing particles and dust.
The outdoor unit also has a fan that pulls air through the outdoor coil. This process allows the system to release heat that has been absorbed from inside the home. Central, split-system, ductless, and packaged air conditioners all use fans.
It is this warm air and moisture that needs to be vented out of the room you are currently cooling. Moreover, the heat extracted from the air has to leave your room, otherwise, it will mix up with the cold air again. Ventless air conditioners are a marketing scam and never work.
Single hose portable air conditioners work by pulling stagnant air from inside the room. The motor inside the unit then cools the air for circulation throughout the space. The unit also takes the excess warm air and moisture and funnels it through the hose and out the window.
The AC uses less energy in fan mode than when cooling. But running the fan all the time can increase the amount of maintenance your HVAC system might need. That's because the filter can clog up sooner and mechanical wear and tear can accelerate.
Since the AUTO setting means the fan is only engaged when the system is on, rather than constantly blowing, AUTO is the most energy-efficient option between the two settings.
Modern whole house fans are quieter and better insulated, but they're still not as common. Today, it's hard for whole house fans to compete with heat pumps and ductless heat pumps, which operate more efficiently and deliver better cooling than either whole house fans or traditional AC systems.
Running the HVAC fan by itself usually does not bring in outside air. The fan's job is to move air around your home. When you set your HVAC to “fan” mode, it circulates the air that's already inside your house. However, some systems have a fresh air intake that can bring in outside air when the fan is running.
Only use your fan when the outdoor air is cooler than your indoor air. Make sure your A/C is off when you run the fan to avoid wasting energy. We recommend running the whole house fan all night. The goal is to cool your entire house down, not just the air.
Does it bring in fresh air? No, air conditioners do not bring in fresh air from the outside. That's not how they were designed. What actually happens is that your air conditioner uses a fan to draw air into the unit and disperse it through a structure.
Locate Your Fresh Air Intake
The air intake is typically an open duct that leads to a vent on a wall outside your home or the attic. There's a small filter inside the vent so it can deliver clean air. This also lessens the demand for other HVAC filters. Depending on your home, it may have multiple fresh air intakes.
Placing a fan in front of your unit helps spread the cooled air.
Not all air conditioners are safe to use when it is smoky outside, such as during a bushfire. Some air conditioners can draw in smoky air from outside, which can be harmful to your health. It's important to understand the type of air conditioner you have so that you know if, and how, to use it when it's smoky outside.
No, an air conditioner does not bring fresh air from outside to the inside of your home. While part of your system may be located outside, if you have a split system, this does not mean it uses the outside air. The primary purpose of your system is not cooling the air; it's to move the unwanted heat out of your air.
Worried about that fog or the mist you see coming from your AC? Don't worry—it usually doesn't mean there's something wrong with your air conditioner. The mist is just condensed water vapor that forms when cold, dry air comes into contact with humid, warm air (we'll explain this in more detail later on).