Where should a hot air furnace return be located?

The location of a hot air furnace return is critical for ensuring efficient heating and proper air circulation throughout a building. Positioning the return by an inside wall allows it to effectively draw in cooler air from the room, which can then be heated by the furnace. This setup encourages the natural flow of warm air rising to the ceiling and cooler air descending to the floor, creating a more balanced temperature distribution.

Having the return near an inside wall means it is also less likely to be influenced by drafts or external temperature variations, as it is somewhat insulated from outdoor conditions. This helps maintain a consistent indoor temperature, which is essential for comfort.

In contrast, returns placed too close to windows may pull cold air directly in from outside, leading to inefficient heating. Those located near the thermostat could adversely affect its readings, mistakenly signaling the furnace to operate longer than needed, which could lead to higher energy costs. Returns positioned high up on an inside wall might not be ideal either, as they might interfere with the natural airflow dynamics intended for the heating system.