Heating and cooling your home uses more energy and drains more energy dollars than any other system in your home. Typically, 44% of your utility bill goes for heating and cooling. What's more, heating and cooling systems in the United States together emit over a half billion tons of carbon dioxide into the atmosphere each year, adding to global warming. They also generate about 24% of the nation's sulfur dioxide and 12% of the nitrogen oxides, the chief ingredients in acid rain.
No matter what kind of heating, ventilation, and air-conditioning system you have in your house, you can save money and increase comfort by properly maintaining and upgrading your equipment. But remember, an energy-efficient furnace alone will not have as great an impact on your energy bills as using the whole-house approach. By combining proper equipment maintenance and upgrades with appropriate insulation, weatherization, and thermostat settings, you can cut your energy bills and your pollution output in half.
Household Heating Systems
Although there are several different types of fuels available to heat our homes, about half of us (53%) use natural gas, 26% use electricity, 11% use fuel oil, and 10% use other methods.
• Set your thermostat as low as is comfortable.
• Clean or replace filters on furnaces once a month or as needed.
• Clean warm-air registers, baseboard heaters, and radiators as needed; make sure they're not blocked by furniture, carpeting, or drapes.
• Bleed trapped air from hot-water radiators once or twice a season; if in doubt about how to perform this task, call a professional.
• Place heat-resistant radiator reflectors between exterior walls and the radiators.
• Use kitchen, bath, and other ventilating fans wisely; in just 1 hour, these fans can pull out a houseful of warmed or cooled air. Turn fans off as soon as they have done the job.
• Keep draperies and shades open on south-facing windows during the heating season to allow sunlight to enter your home; close them at night to reduce the chill you may feel from cold windows.
• Close an unoccupied room that is isolated from the rest of the house, such as in a corner, and turn down the thermostat or turn off the heating for that room or zone. However, do not turn the heating off if it adversely affects the rest of your system. For example, if you heat your house with a heat pump, do not close the vents – closing the vents could harm the heat pump.
• Select energy-efficient equipment when you buy new heating equipment. Your contractor should be able to give you energy fact sheets for different types, models, and designs to help you compare energy usage. Look for the ENERGY STAR® label. The ENERGY STAR® is a program of the U.S. Department of Energy (DOE) and the Environmental Protection Agency (EPA) designed to help consumers identify energy-efficient appliances and products.
What's a BTU?
One BTU, British Thermal Unit, is roughly equivalent to burning one kitchen match. That may not sound like much, but a typical home consumes about 100 million BTUs per year. Approximately one-half of the total is used for space heating.
One of the most important systems in your home, though it's hidden beneath your feet and over your head, may be wasting a lot of your energy dollars. Your home's duct system, a branching network of tubes in the walls, floors, and ceilings, carries the air from your home's furnace and central air conditioner to each room. Ducts are made of sheet metal, fiber glass, or other materials.
Unfortunately, many duct systems are poorly insulated or not insulated properly. Ducts that leak heated air into unheated spaces can add hundreds of dollars a year to your heating and cooling bills. Insulating ducts that are in unconditioned spaces is usually very cost effective. If you are buying a new duct system, consider one that comes with insulation already installed.
Sealing your ducts to prevent leaks is even more important if the ducts are located in an unconditioned area such as an attic or vented crawl space. If the supply ducts are leaking, heated or cooled air can be forced out unsealed joints and lost. In addition, unconditioned air can also be drawn into return ducts through unsealed joints. In the summer, hot attic air can be drawn in, increasing the load on the air conditioner. In the winter, your furnace will have to work longer to keep your house comfortable. Either way, your energy losses cost you money.
Although minor duct repairs are easy to accomplish, ducts in unconditioned spaces should be sealed and insulated by qualified professionals using the appropriate sealing materials. Here are a few simple tips to help with minor duct repairs.
• Check your ducts for air leaks. First look for sections that should be joined but have separated and then look for obvious holes.
• If you use duct tape to repair and seal your ducts, look for tape with the Underwriters Laboratories (UL) logo to avoid tape that degrades, cracks, and loses its bond with age.
• Remember that insulating ducts in the basement will make the basement colder. If both the ducts and the basement walls are uninsulated, consider insulating the basement walls and the ducts.
• If your basement has been converted to a living area, install both supply and return registers in the basement rooms.
• Be sure a well-sealed vapor barrier exists on the outside of the insulation on cooling ducts to prevent moisture buildup.
• Get a professional to help you insulate and repair all ducts.
Ducts – Out of Sight, Out of Mind
The unsealed ducts in your attics and crawl spaces lose air – uninsulated ducts lose heat, wasting energy and money.
If you use electricity to heat your home, consider installing an energy-efficient heat pump system. Heat pumps are the most efficient form of electric heating in moderate climates, providing three times more heating than the equivalent amount of energy they consume in electricity.
There are three types of heat pumps: air-to-air, water source, and ground source. They collect heat from the air, water, or ground outside your home and concentrate it for use inside. Heat pumps do double duty as a central air conditioner. They can also cool your home by collecting the heat inside your house and effectively pumping it outside. A heat pump can trim the amount of electricity you use for heating as much as 30% to 40%.
Heat Pump Tips
• Do not set back the heat pump's thermostat manually if it causes the electric resistance heating to come on. This type of heating, which is often used as a backup to the heat pump, is more expensive.
• Clean or change filters once a month or as needed, and maintain the system according to manufacturer's instructions.
Using the sun to heat your home through passive solar design can be both environmentally friendly and cost effective. In many cases, you can cut your heating costs by more than 50% compared to the cost of heating the same house that does not include passive solar design. Passive solar design techniques include placing larger, insulated windows on south-facing walls and locating thermal mass, such as a concrete slab floor or a heat-absorbing wall, close to the windows. However, a passive solar house requires careful design, best done by an architect for new construction or major remodeling.
• Keep all south-facing glass clean.
• Make sure that objects do not block the sunlight shining on concrete slab floors or heat-absorbing walls.
• Consider using insulating curtains to reduce excessive heat loss from large windows at night.
When you cozy up next to a crackling fire on a cold winter day, you probably don't realize that your fireplace is one of the most inefficient heat sources you can possibly use. It literally sends your energy dollars right up the chimney along with volumes of warm air. A roaring fire can exhaust as much as 24,000 cubic feet of air per hour to the outside, which must be replaced by cold air coming into the house from the outside. Your heating system must warm up this air, which is then exhausted through your chimney. If you use your conventional fireplace while your central heating system is on, these tips can help reduce energy losses.
• If you never use your fireplace, plug and seal the chimney flue.
• Keep your fireplace damper closed unless a fire is going. Keeping the damper open is like keeping a 48-inch window wide open during the winter; it allows warm air to go right up the chimney.
• When you use the fireplace, reduce heat loss by opening dampers in the bottom of the firebox (if provided) or open the nearest window slightly – approximately 1 inch – and close doors leading into the room. Lower the thermostat setting to between 50° and 55°F.
• Install tempered glass doors and a heat-air exchange system that blows warmed air back into the room.
• Check the seal on the flue damper and make it as snug as possible.
• Add caulking around the fireplace hearth.
• Use grates made of C-shaped metal tubes to draw cool room air into the fireplace and circulate warm air back into the room.
Gas and Oil Heating Systems
If you plan to buy a new heating system, ask your local utility or state energy office for information about the latest technologies available to consumers. They can advise you about more efficient systems on the market today. For example, many newer models incorporate designs for burners and heat exchangers that result in higher efficiencies during operation and reduce heat loss when the equipment is off. Check the appliance card in the back of this booklet for additional information on how to understand heating system ratings.
Look for the ENERGY STAR® label.
It might surprise you to know that buying a bigger room air-conditioning unit won't necessarily make you feel more comfortable during the hot summer months. In fact, a room air conditioner that's too big for the area it is supposed to cool will perform less efficiently and less effectively than a smaller, properly sized unit. This is because room units work better if they run for relatively long periods of time than if they are continually, switching off and on. Longer run times allow air conditioners to maintain a more constant room temperature. Running longer also allows them to remove a larger amount of moisture from the air, which lowers humidity and, more importantly, makes you feel more comfortable.
Sizing is equally important for central air-conditioning systems, which need to be sized by professionals. If you have a central air system in your home, set the fan to shut off at the same time as the cooling unit (compressor). In other words, don't use the system's central fan to provide circulation, but instead use circulating fans in individual rooms.
• Whole-house fans help cool your home by pulling cool air through the house and exhausting warm air through the attic. They are effective when operated at night and when the outside air is cooler than the inside.
• Set your thermostat as high as comfortably possible in the summer. The less difference between the indoor and outdoor temperatures, the lower your overall cooling bill will be.
• Don't set your thermostat at a colder setting than normal when you turn on your air conditioner. It will not cool your home any faster and could result in excessive cooling and, therefore, unnecessary expense.
• Set the fan speed on high except in very humid weather. When it's humid, set the fan speed on low. You'll get better cooling, and slower air movement through the cooling equipment allows it to remove more moisture from the air, resulting in greater comfort.
• Consider using an interior fan in conjunction with your window air conditioner to spread the cooled air more effectively through your home without greatly increasing your power use.
• Don't place lamps or TV sets near your air-conditioning thermostat. The thermostat senses heat from these appliances, which can cause the air conditioner to run longer than necessary.
• Plant trees or shrubs to shade air-conditioning units but not to block the airflow. A unit operating in the shade uses as much as 10% less electricity than the same one operating in the sun.
The shopping guide in the back of this booklet will help you find the right size unit for your needs. Look for the ENERGY STAR® label.
You can save as much as 10% a year on your heating and cooling bills by simply turning your thermostat back 10% to 15% for 8 hours. You can do this automatically without sacrificing comfort by installing an automatic setback or programmable thermostat.
Using a programmable thermostat, you can adjust the times you turn on the heating or air-conditioning according to a pre-set schedule. As a result, you don't operate the equipment as much when you are asleep or when the house or part of the house is not occupied. (These thermostats are not meant to be used with heat pumps.) Programmable thermostats can store and repeat multiple daily settings (six or more temperature settings a day) that you can manually override without affecting the rest of the daily or weekly program. When shopping for a programmable thermostat, be sure to look for the ENERGY STAR® label.
Using a programmable thermostat, you can automatically turn down your heat at night or when you are not at home.
In the summer, you can save money by automatically turning your air- conditioning up at night.
For more information on heating and cooling, contact:
Air Conditioning and Refrigeration Institute,
(888) STAR-YES (782-7937)
Owens Corning Customer Service Hotline,
(800) GET-PINK (438-7465)
U.S. Department of Energy's
Energy Efficiency and Renewable Energy Clearinghouse (EREC), (800) DOE-EREC (363-3732), and Network (EREN).
Source: U.S. Department of Energy