Vexed by Vents?
Proper Placement And Installation Is Vital For Ventilation
Every heating and cooling season homeowners and contractors alike are baffled with trying to figure out fluctuating room temperatures. It’s a strange and sometimes irritating phenomenon. While one room of the house is the perfect temperature another may be hot and uncomfortable or cold and damp depending on the specific season. The fact is that every room of the house settles at a different temperature, but it can drive your energy bills too high trying to compensate.
In this article, Horizon Services experts clear the air and give you the cold, hard facts of how the proper placement and installation of supply registers is vital for ventilation.
Return Vents and Return Grilles
Homes that use forced air for both heating and cooling purposes will have return vents and supply registers. The main function of the return vent is to deliver air, via grilles and ductwork, back to the furnace so that it will run as designed. Return vents also help provide proper air circulation throughout the physical structure.
Location, Location, Location.
So, why is the location of ductwork important? Location is important because ducts placed in unconditioned areas such as attics, basements, garages, or crawl spaces ultimately waste energy if improperly insulated—another major cause of energy loss. Additionally, most homes have leaks in both the return and supply sides of the duct system. Locating ductwork in conditioned spaces decreases the temperature difference if for some reason leaks do occur.
Size, Location, and Length Does Matter
The size, location, and length of heating, ventilating, and air conditioning (HVAC) registers and ductwork are determined by measurement of air movement at cubic feet per minute (CFM). Whatever the CFM output of the heating or cooling system, the air return vents must be able to provide the same CFM ratio. Additionally, for maximum heating and circulating efficiency, there should be properly-sized return vents in each room where heating registers are located.
For example, a well-placed supply register delivering 100 CFM of airflow can easily condition 800 to 1400 cubic feet of room air depending on the insulation factor and tightness of the home. The principle behind this is that higher velocity supply air coming out of the register entrains the air of the room and mixes these two bodies of air together. This is referred to as air entrainment. How well this air entrainment is accomplished is determined by how well the register allows air from the duct system to mix with the air in a room.
The Importance of Supply Registers
Supply register are necessary to prevent a buildup of pressure in the structure that may lead to various health problems, as well as preventing mold and mildew, and deterioration of the structure itself due to moisture buildup. As warm air is forced into a room, it replaces cold air already in the room. This cooler air must be pushed out of the room; otherwise the room becomes uncomfortably over-pressurized. The cooler air is, in turn, forced into the return vent, back to the furnace, reheated, and returned to the cycle.
Additional Ways To Save on Energy Costs
Evaluating the efficiency of your ductwork, checking for air leaks in seams and joints in the duct, is just one way to save on energy costs. For more information about HVAC systems, other appliances, and additional resources for improving your home’s overall energy efficiency, please refer to other Horizon Comfort Zone articles.