let's know more about "Do home HVAC systems use outside air". Usually, in many HVAC systems, there is an indoor and outdoor part, where the outer part is a big box that is bigger than the inner part. Many people believe that in this large box the fresh air from the outdoors is ventilated and brought into the house, but what is the reality? If so, this issue can be a concern on days when the air outside is polluted and full of dust. Many air conditioners do not draw air from the outdoors. In the following, we will explain the operation of the air conditioner and how they bring cold air into the house.

How does the HVAC system work?

In many HVAC systems, indoor air is usually absorbed, heated, or cooled in the system, and then circulated at the desired temperature.

Producing cool air

On hot days, the warm air inside the house is absorbed by a component named a compressor, and then this hot air is cooled by a liquid called a refrigerant, which is placed in a closed metal ring that helps circulate the warm air from the house to the outside and brings the cold air back inside.

The steps to create cold air are as follows:

  • First, the compressor absorbs the warm air inside the house and then cools it using refrigerant.
  1. This hot air heats the refrigerant. For this reason, the refrigerant moves the hot air outside and is exposed to the cool outside air.
  2. After removing this warm air outdoors, the cool refrigerant is returned indoors.
  3. The refrigerant passes to the evaporator using a thin valve in the HVAC-R system, which is held at low pressure and induces the refrigerant to expand, and the refrigerant becomes very cold.
  4. After that, the fans located in the duct of the system distribute cool air throughout the house.

Producing warm air

The procedure of an HVAC system to heating a house is typically much simpler than cooling it. A furnace inside the system has burners that make combustion gases that exit via the heat exchanger. As it exits the heat exchanger, a fan blows air over these hot gases and distributes them via ducts in the house.

Reasons for bringing fresh air inside

HVAC is not accountable for bringing fresh air in from outdoors. Yet, many factors and parameters can cause fresh air to enter:

Architectural defects

Outside air can enter the building through architectural defects such as cracks in the walls, floor, roof, and trim around entrances and windows, and accumulates over time. To solve this problem, you need to repair the gaps and lines on the walls.

Extra ventilation

Usually, a large amount of air is transferred between inside and outside via open doors and windows. An outdoor vented fan utilized to exhaust air from a room, such as a bathroom fan or a kitchen fan, can yield this problem.

DOAS Systems

Although most HVAC systems do not carry fresh air into the building, some HVAC systems utilize outside air for the heating and cooling procedure. These classes of HVAC systems are growing, as there are some eco-friendly advantages associated with indoor and outdoor dual-ventilation systems. DOAS systems utilize parallel ventilation of indoor and outdoor systems to distribute air inside and outside the building. This procedure brings fresh air into the building via mechanical means, which is done in one of the following two ways:

1. Separate systems with separate ductwork

In this procedure, the indoor and outdoor parts of the HVAC unit divide the work of heating and cooling the house. Although this type of system has a high initial expense for installation and operation, by using it, it is easier to handle the flow of outside air into the house. It also decreases the load on the fan coil units, which weakens single-direction air conditioning systems.

2. Combined system

These settings cause the cold outside air to enter directly into the ductwork, which circulates again inside the house. Then it blends with the indoor air that is circulated by the fan coil units and cools the return air that goes inside the house.

In this method, it can be difficult to balance the airflow that leaves the house and travels inside, but the initial installation expenses will be lower than with a separate duct system. In addition, the combined external/internal airflow reduces the volume of airflow and thus helps to save energy costs related to the use of fans.

Was Do home HVAC systems use outside air Useful for you? leave a comment and tell your Viewpoint

Related Posts

Leave a Reply

Your email address will not be published. Required fields are marked *