Types of Heating Systems
A variety of technologies are available for heating your house. In addition to heat pumps, which are discussed separately, many homes use the following approaches:
Furnaces and Boilers
By far the most common way to heat a home.
Wood and Pellet-Fuel Heating
Provides a way to heat your home using biomass or waste sources.
Electric Resistance Heating
Among the most expensive ways to heat a home.
Active Solar Heating
Uses the sun to heat either air or liquid and can serve as a supplemental heat source.
Can draw on a number of energy sources, including electricity, boilers, solar energy, and wood and pellet-fuel heating.
Small Space Heaters
Less efficient than central heating systems, but can save energy when used appropriately.
While forced-air heating systems rely on the same type of ducts used by heat pumps and air conditioners, water and steam heat systems use radiators that only deliver heat.
Heat Distribution Systems
Heat is distributed through your home through a variety of ways whether forced-air systems, central air-conditioning, heat pump systems, radiant heating, steam radiators, or hot water radiators.
Types of Central Air Conditioners
A central air conditioner is either a split-system unit or a packaged unit.
In a split-system central air conditioner, an outdoor metal cabinet contains the condenser and compressor, and an indoor cabinet contains the evaporator. In many split-system air conditioners, this indoor cabinet also contains a furnace or the indoor part of a heat pump. The air conditioner's evaporator coil is installed in the cabinet or main supply duct of this furnace or heat pump. If your home already has a furnace but no air conditioner, a split-system is the most economical central air conditioner to install.
In a packaged central air conditioner, the evaporator, condenser, and compressor are all located in one cabinet, which usually is placed on a roof or on a concrete slab next to the house's foundation. This type of air conditioner also is used in small commercial buildings. Air supply and return ducts come from indoors through the home's exterior wall or roof to connect with the packaged air conditioner, which is usually located outdoors. Packaged air conditioners often include electric heating coils or a natural gas furnace. This combination of air conditioner and central heater eliminates the need for a separate furnace indoors.
Choosing or Upgrading Your Central Air Conditioner
Central air conditioners are more efficient than room air conditioners. In addition, they are out of the way, quiet, and convenient to operate. To save energy and money, you should try to buy an energy-efficient air conditioner and reduce your central air conditioner's energy use. In an average air-conditioned home, air-conditioning consumes more than 2,000 kilowatt-hours of electricity per year, causing power plants to emit about 3,500 pounds of carbon dioxide and 31 pounds of sulfur dioxide.
If you are considering
Adding central air-conditioning to your home, the deciding factor may be the need for ductwork.
If you have an older central air conditioner, you might choose to replace the outdoor compressor with a modern, high-efficiency unit. If you do so, consult a local heating and cooling contractor to assure that the new compressor is properly matched to the indoor unit. However, considering recent changes in refrigerants and air-conditioning designs, it might be wiser to replace the entire system.
Today's best air conditioners use 30% to 50% less energy to produce the same amount of cooling as air conditioners made in the mid-1970s. Even if your air conditioner is only 10 years old, you may save 20% to 40% of your cooling energy costs by replacing it with a newer, more efficient model.
New residential central air conditioner standards
went into effect on January 23, 2006. Air conditioners manufactured after January 26, 2006 must achieve a SEER of 13 or higher. SEER 13 is 30% more efficient than the previous minimum SEER of 10. The standard applies only to appliances manufactured after January 23, 2006. Equipment with a rating less than SEER 13 manufactured before this date may still be sold and installed.
The average homeowner will remain unaffected by this standard change for some time to come. The standards do not require you to change your existing central air-conditioning units, and replacement parts and services should still be available for your home's systems. The "life span" of a central air conditioner is about 15 to 20 years. Manufacturers typically continue to support existing equipment by making replacement parts available and honoring maintenance contracts after the new standard goes into effect.
Other features to look for when buying an air conditioner include:
Selecting a New Water Heater
You have a lot to consider when selecting a new water heater for your home. You should choose a water heating system that will not only provide enough hot water but also that will do so energy efficiently, saving you money. This includes considering the different types of water heaters available and determining the right size and fuel source for your home.
Types of Water Heaters
It's a good idea to know the different types of water heaters available before you purchase one: