Provided you have a compatible system, Ecobee smart thermostats support cross ventilation through their Free Cooling feature. You can also get similar functionality from whole-house ventilation ...

Install exhaust fans in bathrooms and kitchens Open windows regularly to let in fresh air Use ceiling fans in high-humidity areas Consider a whole-house ventilation system for constant airflow ...

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.