How to Ventilate Well - Daikin

How to Ventilate Well

Created on 28 April 2020


We, Daikin, as the professional in air and air conditioners, would like to share useful information to stay healthy and active by ventilating rooms.

1. Fundamental Knowledge about Ventilation

  • What is Ventilation?
  • What are Pollutants?
  • Why do we need to Ventilate?
  • Don’t Air Conditioners Ventilate?

2. Tips for Ventilation

- What can I do to Ventilate Rooms? 
1. Let’s use 24 hours ventilation system properly which you might already own.

2. Let’s open the windows to let the airflow.

3. Let’s utilize the ventilation fan in the kitchen.

Home Ventilation Methods Summary

1. Fundamental Knowledge about Ventilation

What is Ventilation?

  • By replacing the air inside the rooms and the air outside the rooms, the air inside which polluted (or substances which harm human) to dilute or letting push out.

What are pollutants?

  • Pollutants (or substances which harm human) include carbon dioxide (CO2), carbon dioxide (CO), formaldehyde (HCHO), house dust, pollen, bacteria, and viruses. By ventilate the air inside the rooms, we can expect these pollutants may push out from the room or diluted.

Why do we need to Ventilate?
1. It is to dilute or push out the pollutant.
In a completely closed room, the air is hard to get out of the room, so pollutants will remain in the room or keep increasing. And that air has a bad effect on humans. Ventilation is very important to get these pollutants out of the room and to dilute them

2. If we do not do anything, dirty air will accumulate in the room.
Many of the houses you live in, such as houses and condominiums, are highly airtight, and it is difficult for the dirty air to leave the rooms. In such a house, if we do not do anything, the room will be insufficient ventilation, and dirty air will accumulate in the room.

Don’t Air Conditioners Ventilate?
- Do you think that the air coming out of the air conditioner is taken-in from outside the house? You might be understood that if you operate the air conditioner you can ventilate? 
- An air conditioner creates a comfortable environment by “inhaling the air in the room”, cooling it or warming it, and then returning it to the room. The air inside and outside the room is not exchanged usually. Therefore, most air conditioners cannot ventilate.
Ventilation should be done other than using air conditioning.

2. Tips for Ventilation

(1) Let’s use 24 hours ventilation system properly which you might already own.

- If your home or condominium was built after July 2003, it will have a ventilation mechanism (ventilation port, 24-hour ventilation system). However, there are many cases where it is not used correctly. There are “ventilation openings” on the walls and ceiling of the room. If you are living and use a ventilation fan for a bath, toilet, washroom, etc., the dirty air inside the room will be discharged from the building (exhaust air) through the ventilation opening, and at the same time take in new air from the outside of the building. Designed for (air supply). This ventilation system is the most common type of ventilation in homes and condominiums, and it takes two hours to completely change the air in the room. First of all, it is basic to use the existing 24-hour ventilation system properly.


Example of a 24-hour ventilation system




However, if you close the ventilation port or turn off the 24-hour ventilation system because the air comes in from the outside and it is cold (or hot), the ventilation system can not play a role, Unknowingly, the air in the room accumulates dirt. Ensure that the ventilation system is open and the 24-hour ventilation system is always on and in “correct” use.

(2) Let’s open the windows to let the airflow.

- It is said that the time and the number of times to open a window and ventilate is about 5 to 10 minutes per hour. However, since the speed of airflow depends on the size of the window or room and the type of pollutant floating in the room, the exact effectivity of how much ventilation will surely reduce the risk of infectious diseases is uncertain.

In addition, the effect of ventilation is higher by performing ventilation for 5 minutes twice an hour than performing ventilation for 10 minutes once in 2 hours.

If you are concerned about pollen when opening windows, you can suppress pollen intrusion to some extent by placing an air purifier near the window. In addition, lace curtains are said to be effective as a measure against pollen.

For the case when it is still difficult for air to enter despite the opening window 
- As wind or air tend to enter a space through a small gap and exit easily through a large gap (with a small force), by opening the window slightly on the side where air enters an opening window widely on the side where air exits can increase the effectiveness of ventilation.



Window-opening trick for when is  it  difficult for air to enter (entering small, exciting big)

For the case when only 1 window can be opened
- In the case where only 1 window can be opened, by opening the room door and positioning a fan to face outside will increase the effectiveness of ventilation. By positioning the fan to face outwards is the best way to ventilate indoor air. If the fan was positioned facing inwards, it allows outside air to enter the room, but dirty indoor air will not be able to be expelled outside.


When there is only 1 window, create airflow by placing the fan next to the window

For the case of window-less room 
- For rooms without windows, opening the door and placing a fan to let the air flow out. By operating ventilators installed in the bathroom, washrooms, and toilets, etc, the air from other rooms will also be effectively expelled out.


Ventilation method for window-less rooms

(3) Let’s utilize the ventilation fan in the kitchen

- Ventilation can also be done effectively by using the ventilator installed in the kitchen, which has the largest ventilation capacity in residences. In this case, if you open windows near the kitchen, it is difficult to ventilate the air throughout the room, so try opening windows located as far from the kitchen as possible. Even by having 2 windows open and switching on the ventilator in the kitchen, it facilitates ventilation in the room. Hence, it is recommended to open windows while operating the ventilator.

Home Ventilation Methods Summary

Effective ventilation can be done by using a combination of methods 1~3, depending on your living environment.

When you want to ventilate the entire house
- It is best to open a window located either on the balcony or entrance side, and keep other doors along the path opened.


If you want to ventilate only the living room (if you cannot open the entrance window)
- Open two windows on the left and right that face the balcony.
* When ventilating with a balcony window, even if you open one place, no air will flow in or out, so open both ends to allow the air to flow. ควรเปิดทั้ง 2 ฝั่งเพื่อให้อากาศหมุนเวียนได้
- If the wind still does not flow, operate the kitchen ventilation fan (range hood). The balcony window opens a part of the window away from the range hood.


Open two windows (both ends) facing the balcony.


Partially open the kitchen ventilation fan (range hood) and the window facing the balcony (window away from the kitchen)

As Daikin is a company that is “Perfecting the Air,” we will continue to communicate the importance of Air.