When you run your air conditioning is it cool downstairs, but feels like a sauna upstairs?

This happens because hot air is more buoyant and rises, while cold air is denser and falls. The thermostat is on the main floor and will reach the set temperature, while the upper floor can be significantly hotter and basement significantly colder.

You can make your home a more even temperature by:
1. Closing air vents fully in the basement, partially on main floors and leaving them wide open on upper floors. This will cause more cold air to be forced to the upper floors where it will fall and create a more even temperature throughout your home.
2. An even more effective option is to leave your furnace fan setting in the on position, which will continuously circulate the air in your home. Constantly running your furnace fan will add around $5-$10 a month to your hydro bill but is well worth it in terms of comfort.
3. Keeping air return ducts from being blocked or restricted will allow your HVAC systems to circulate air as intended.
These tips can also be used in heating season by doing the opposite of step one (Vents wide open in basement, half open on main floor and closed on upper floor)