Ventilate: When to Open

Ventilate tells you when to open or close each window to cool your home with outdoor air, and where to place a fan. It is designed for hot homes in summer and during heat waves, with or without air conditioning. Open when outdoor air is cooler than the room. Close when it is warmer, so your home does not pull in heat. If you have AC, check the windows first: when outdoor air can do the work, you can run the AC less. Ventilate does not estimate your electricity bill. USE IT TO • Cool a house or apartment without AC: it tells you when outdoor air is cooler than the air inside. • Use less AC: open windows first when outdoor air can do the work. • Cool your home at night: it tells you when night air can flush out the heat, and when it cannot. • Get through a heat wave: it tells you which windows to keep closed, including windows facing the sun. • Place a fan: with windows on one side, place a floor fan on the sill facing into the room. With windows on opposite sides, face the fan out of the exhaust window to pull cooler air through your home. HOW IT WORKS • It compares the local forecast with the indoor temperature you record. • It knows which direction each window faces, so sunlight on that side counts. • Each window gets one recommendation: close, crack open, open wide, or add a fan. • The advice follows the forecast throughout the day instead of using a fixed schedule. • A reminder arrives before the next recommended change. • It provides advice only. It does not control an air conditioner, thermostat, or smart home device. ON YOUR IPHONE • The dashboard shows how your indoor temperature has changed since yesterday. • History covers indoor and outdoor temperatures over 24 hours, 7 days, and 30 days. • A Home Screen widget and Live Activity show the advice without opening the app. • Ask Siri what to do with your windows or when the next change is, or record your indoor temperature by voice. The same actions work in Shortcuts. • Guides cover hot nights and heat waves. SETUP No account required. Point your iPhone at each window once so Ventilate can record which direction it faces. Record your indoor temperature whenever you can. A thermometer helps, but you can start without one. The forecast requires an internet connection. VENTILATE PRO OPTIONAL SUBSCRIPTION • Adds outdoor air quality, UV index, and humidity to the dashboard, plus pollen information in Europe. • When outdoor air is cooler but polluted or muggy, it opens the window less or keeps it closed. • On days with high UV levels, it closes windows facing the sun. • If you say you are sensitive to pollen, windows open less on high-pollen days. • Adds the next 24 hours as curves showing window advice and outdoor conditions. Window advice, history, the widget, and the guides are included without a subscription. Payment is charged to your Apple ID account upon confirmation of purchase. The subscription renews automatically unless canceled at least 24 hours before the end of the current period. You can manage or cancel subscriptions in your App Store account settings. Terms of Use: https://getventilate.app/terms Privacy Policy: https://getventilate.app/privacy