I was shocked the other morning when I took the vent cover off of, what I thought was a heat register in my family room.
I figured that I should vacuum out the vents before I turned on the heat for the first time. I was new to the house and this would be the first winter season season living there. Imagine my surprise when I realized that there was no duct labor there. It was certainly open to the other side of the wall where there was an identical vent cover. I thought at first that someone just put them there for decorative purposes however when I asked the proprietor about them he explained that the vest covers and pass through were to allow for cold air return. The heat came from the vents in the ceiling and it was drawn down by the cold air returns. The air was then sucked back into the heating system to be warmed again. This natural flow of boiling and cool air allowed for even heating. Years ago, before HVAC systems were installed, they used floor vents and wall vents to circulate the boiling air throughout the house. It is still used in numerous areas where it is impossible to install modern equipment. Warm air rises, cool air falls, it is just the nature of things and if you can use this process to provide you an even boiling temperature, this is all the better. If you have efficient, “drafting”, as it is called, you can certainly save a lot on your energy bills too.