Does HVAC Bring In Fresh Air

Does HVAC Bring In Fresh Air
  • Author: Amanda Arnold
  • Posted On: September 22, 2021
  • Updated On: August 21, 2023

Many people believe that air conditioners bring fresh air in from outside the house. When there are high pollen days or many contaminants in the air, this might be a source of anxiety for certain people.

Most air conditioners do not draw air from outdoors. In this article, we will discuss the complete working mechanism of the HVAC to know about the entrance and exit of the air.

Even to the most ardent fans, the working of a heating and cooling system is often a mystery. For various reasons, including comfort, indoor air quality, and ventilation, homeowners frequently wonder how their system brings cold air into their homes.

Is air drawn in from the outside to be distributed? Surprisingly, that isn’t exactly how it works. We are here to answer all these questions. So, let’s start discussing each parameter in detail:

What Does The Come In The Heating Or Cooling System?

If you look closely at your air conditioner, you’ll notice that it has an interior and an external component, both of which are connected by copper cables. These copper wires load with either liquid or gaseous refrigerant.

The only thing that passes between the two units is that. The air surrounding your outside unit is simply outside air, while the air from your interior unit is simply inside air.

It’s a frequent misperception that air conditioners bring air in from outside. Although some air conditioners have components outside, they do not draw in outside air. Instead, air conditioners use a heat pump to transfer heat to the outside. The air from your air conditioner is simply your room’s air.

Your air conditioner circulates and cools it regularly. Using a heat pump, your AC unit extracts the heat from this air and pushes it outdoors. The refrigerant then cools the air before being returned to the unit’s return air intake.

The Basic Working Parameter Of AC Unit

An air conditioner return air inlet is usually situated on the ceiling of the indoor area of your unit. This return air intake grille usually has a filter to keep dust and debris out while allowing air to flow through.

The air enters the unit through the filter and swiftly passes across the supercooled coils. Before the now-cold filtered air is sent back into your home, the heat is transferred out of the air and into the coils.

You may confirm this by measuring the dust particles in your ambient room air vs. the air coming out of your AC unit with a particle tester. Because of the AC filter, it will be precisely the same, if not a little cleaner. Air conditioners that don’t bring in fresh outdoor air are a big plus for pollen allergy sufferers.

Bringing in outside air can expose you to pollen and particulate matter, both of which can damage your health. Because the air in your room is filtered frequently by your AC unit, recirculating it ensures that it is primarily free of pollen and dust.

Reasons Behind The Entrance Of Fresh Air Inside

Well, HVAC is not responsible for entering the fresh air inside from outside. However, there are several aspects and parameters that can cause for entering the fresh air inside:

1) Cracks In The Building

Through architectural flaws, a small amount of air is allowed to enter the building. Small amounts of air will constantly enter the structure through cracks and crevices in the framing, walls, floors, ceiling, and trim around the doors and windows, accumulating over time.

That’s why you have to fix the cracks and lines in the walls if you really don’t want to enter the outside air inside.

2) Additional Ventilation

The most common route for significant amounts of air to travel between the interior and exterior is through open doors and windows. An outdoor-vented fan used to remove air from a single room, such as a deodorizing fan in the bathroom or a smoke-removing fan in the kitchen, could cause this.

Similarly, your outdoor unit draws air in with a fan, removing the heat from the refrigerant and enabling it to cool before being recycled. The air travels through the outdoor unit, absorbing heat and continues on its route.

3) DOAS Systems Use The Outside Air For Heating Or Cooling

While most HVAC systems do not introduce fresh air into a building, the EPA adds that some HVAC systems use outdoor air in the heating and cooling process.

Dual indoor and outdoor ventilation devices are becoming increasingly popular due to the environmental benefits they provide. DOAS systems use parallel ventilation of interior and outdoor units to flow air into and out of your home.

Now that you know a bit more about how air conditioners work, you can see that any problems with air quality you may be experiencing are limited to your home.

If you’re having trouble with indoor air quality in your house, you may need to make extra efforts to clean it up so that your air conditioner doesn’t keep recirculating allergens. However, it’s totally up to you to hire professionals or maintain the HVAC system yourself for better performance.

Final Verdict

In general, a building’s HVAC system does not supply fresh air. Recycled indoor air can use the heat and cool a place, and outdoor HVAC systems are used to expel air rather than to bring it in.

However, DOAS systems are becoming more common and will bring some outside air into your home via mechanical processes. In short, most HVAC units still recycle internal air in a one-way process. If your HVAC system pulls in or out the fresh air, it will surely need quick maintenance.

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Author: Amanda Arnold

Amanda has been working with ConstructionHow since 2021. Her experience spans over 5 years in the creative niche such as home decor and trends, landscaping, renovations, and custom architectural values. As a home designer expert, she has a keen eye for the latest home improvement trends with accurate facts that readers find impossible to ignore. Being invested in home-building trends is how she has gained her lucrative expertise exploring more to bring a positive ambiance for all homeowners (and even tenants!). Currently, she lives in a beautiful beach home, a source of fascination for her.