What Are Cold Air Returns and Why You Need Them

Does your home use gas-forced heating? If so, you will have cold air return vents in addition to your registers or heating vents.

Cold air return vents are designed to return cold air from registers back to the furnace, so it operates correctly. This is what provides proper circulation throughout your home.

Return vents are necessary to prevent problems from arising, such as pressure buildup, proper airflow to avoid sickness, mold, mildew and other household problems, as well as keep the systems within the home working properly. When warm air enters a room, it has to have some way of circulating or the room would over-pressurize. The cooler air is forced out through the cold air return vents, and the cycle begins again.

This process is mandatory for your home to remain healthy. The air being pushed into your home must equal the air leaving your home, or dangerous fumes may backup into different parts of your home. If your vents are evenly spaced and operating efficiently all through your home, air will find a way to travel from room to room, and it won’t be in the most efficient way. That defeats the purpose of a gas-forced heating system.

If you find the cold air return vents throughout your home, you’ll notice they are on the inside walls at the lowest points. That’s because cold air settles near the floor while warm air rises. Unlike supply vents, return vents push cold air back into the system, so they don’t need to be cased in metal. You’ll find them placed in different areas such as in closets, staircase cavities, or other areas where they remain out of the way. Never close off registers or returns trying to control air through the vents; it limits the airflow of the heating system, which causes negative pressure changes.

While cold air return vents should be placed on interior walls near the floor, air flow vents and registers are often scattered throughout the rooms. Never place a vent or register within 10 feet of the thermostat, as the air movement may register a wrong reading and cause your furnace to operate inefficiently.

Also, use exhaust fans in both kitchens and bathrooms to keep the high moisture content out of the rooms. This can increase your chance of mold and mildew, as well as impacting how clean your air supply is. If you have an older home, an energy audit is a great way to ensure your systems are operating properly.

Are your cold air return vents in the proper place throughout your home?