There was a time in my life when I thought, like many of my customers, that closing a bedroom door would keep the room cooler in the Summer, and warming in the Winter. You wouldn't believe how often I am asked if closing the door will lower the air conditioning bill. The same goes to someone trying to reduce costs by closing an air register.
The simple answer to both those questions is don't do it - and here's why. Generally speaking, by shutting the door to a room, you actually restricting the free flow of air within that room and thus, lower the total efficiency of the total system. Most home, but not all, have only one or two air return grill located centrally in the home, which returns the air being pumped into a room back into the system for recirculation.
- When doors are shut, air tries to escape the room under doorways, as shown above.
Berkun Air of West Palm Beach
Today's air conditioners and forced air furnaces move large volumes of air - between 1,000 and 2,000 cubic feet of air every minute. To put this into perspective, this is equivalent to moving between 1,000 to 2,000 14-inch balloons every minute the air conditioning unit / furnace is on. That's a lot of balloons moving around the home.
Everyone knows that if you place your mouth over the top of a soda bottle, and try to blow air into it, you can't do it. You simply pressurize the bottle. The same can be said about closing a bedroom door. The air conditioning unit tries to pump air into room but can't, because there is no place for the air to go. Most people also believe that that small crack at the bottom of the door allows the air to escape that room and return to the air handler. Well, yes and no. For the system to be balanced, that crack under the door would have to be between 5" and 6" in height. The wife isn't going to like that now is she! For every cubic foot of air forced out of a building, a cubic foot of air must be drawn in from outside to replace it.
- Closed off bedrooms can cause negative pressures in other parts of the house, resulting in water heater back drafts contaminated with carbon monoxide.
The problem just gets worse in other parts of the home. For every balloon full of air that the system is trying to pump air into that closed off bedroom, the air handler is trying to suck air back into the system via the return air grill. Because the system is now unbalanced, the return air is creating a vacuum of negative pressure in other parts of the house. Like water, air under pressure will seek the path of least resistance and literally suck air from any place it can get it. This includes vents in bathrooms and kitchen vents, the dryer exhaust vent, cracks in exterior doors, loose windows and exhaust vents for gas water heaters. Your system is now pulling warm air from outside into the home, and worse, contaminated air that may be ladened with carbon monoxide. In turn, utility bills go up, comfort goes down, and health problems proliferate.
Newer air condition duct rules make homes more efficient - lower costs
In 2006, the State of Florida instituted new building code requirements for air conditioning systems called the Balanced Return Initiative. These new building codes were instituted because so many people were practicing poor air conditioning habits that were simply costing them money and energy. The new rules required all rooms that had doors to have both a air conditioning register, and a separate return air resister. In this setting, it didn't matter if the door was open or shut.
This new building code requirement applies to new construction, remodeling efforts that are more than 50% of the value of the existing home and/or when duct work needs to be replaced due to damage and/or mold. The new initiative applies to all rooms with doors, but excludes kitchens, bathrooms and/or laundry rooms.
- Jeff Berkun - Owner
- Berkun Air is a Platinum Level Trane Comfort Specialist and one of just a few in Palm Beach County.
Since 1999, Berkun Air has served the commercial and residential air conditioning needs for Palm Beach County residences. Our factory trained technicians are NATE certified and ARE NOT paid commissions to sell you what you don’t need. Trane’s own customer satisfaction survey results showed that 99.6% of those that have used Berkun Air would recommend us again to others, thus earning us to be a part of Trane’s elite group as certified ”Trane Comfort Specialists” for Palm Beach County. Additionally, Berkun Air maintains an “A+ Rating” with ZERO complaints with the Palm Beach County Consumer Affairs Division. If you need trustworthy help with your air conditioning needs, give us a try. We're here for the long haul and want your repeat business. We can be reached in Palm Beach County by calling (561) 842-4362 or drop us a line via our contact us page.
