How can we keep our rooms ventilated while using the air conditioner?

This is part 17 of our coronavirus FAQ. Click here to read other installments: #Coronavirus the facts. Find the latest information and answers from experts on everything COVID-19.

As summer begins, some people may be worried about keeping air conditioned rooms sufficiently ventilated. Most home units simply recirculate air and do not have ventilation functions. Windows are typically kept closed when they are in use.

Combining natural ventilation with air conditioning

Yamamoto Yoshihide, an associate professor at the Tokyo Polytechnic University and a member of the Architectural Institute of Japan, specializes in air conditioning and ventilation planning for buildings. He suggests that people crack their windows when using air conditioners at the start of summer, when temperatures are not too high. He recommends closing the windows only once the room gets too hot.

Use of fans inside

In the middle of summer, when the risk of heatstroke is highest, Yamamoto recommends we use in-house ventilation systems, such as those in the kitchen and bathroom, instead of opening windows.

Such systems are usually designed to take in outside air, creating circulation even if windows are shut. Talk to experts or your building manager to learn more about ventilation systems.

For your reference:
Backstories: How to beat heatstroke amid coronavirus pandemic


Report: Air conditioning could spread virus. (0:53)