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Before you buy...
Cooling
Related Product Advice
Air conditioning has increased in popularity over the last several decades. Once considered a luxury appliance, now a cooling system is standard equipment in two-thirds of American homes. This includes homes in areas not traditionally associated with cooling needs such as New England and the Pacific Northwest. The cost of for air cooling to homeowners nationwide is over 10 billion dollars.
Air cooling comes in four methods:
Evaporative Cooling – In dry climates evaporative cooling is a favorable option. Evaporative cooling is preferred because it does not use any refrigerants, costs significantly less to install and uses approximately 25% of the energy that unitary air conditioning systems use. It also introduces humidity to the air which is beneficial in dry climates. Evaporative coolers (also called swamp coolers) reduce the air temperature of outdoor air moving through them, by allowing the air to pass through water-soaked pads that humidify the air. Although these systems do use a considerable amount of water, the humidification benefits and low energy use makes evaporative cooling an appropriate alternative to central air conditioning.
Central Air Conditioning –The two most common types of central air conditioning systems are split systems, where the condensing unit is placed outside the house and the evaporator coil inside, and packaged air conditioners that combine the condensing unit and the evaporator coil into one outdoor unit. Properly sizing whatever system is chosen for the home will save on material costs and help to create a more comfortable home. Even conservatively oversized air conditioners that cost more to purchase create humidity problems, because they cycle off before they have a chance to dehumidify the air. This is uncomfortable for the homeowner and, if serious enough, may contribute to diminishing indoor environmental quality. Oversized units are also poor energy performers. Rules-of-thumb, such as 600 square feet of cooled area per ton of air conditioning, don’t work for estimating air conditioning needs accurately.
Room Air Conditioners – Under some conditions, using a room air conditioner may be more efficient then using a central air conditioner. When a house is small and tight it may be difficult to get a central air conditioning system small enough to be efficient. In that case a single room air conditioner may be adequate.
Select central air conditioning units with an ENERGY STAR® rating. ENERGY STAR® air conditioners are at least 20% more efficient than standard equipment and have a Seasonal Energy Efficiency Rating (SEER) of 12 or higher. The SEER rating is usually shown on the yellow and black Energy Guide sticker attached to the unit’s exterior. Also consider that for an air conditioner to be efficient it must be the proper size. This sizing should take into consideration the size of the home as well as the percentage of window coverage. The air conditioner should have to operate at maximum capacity to keep the home cool on the hottest day. To increase the operating efficiency of an air conditioner or heat pump, consider installing units with multi-speed compressors and with variable speed indoor handling units. They can achieve SEER ratings of up to 17 and the cost is generally about 30% higher than standard units. Added advantages include quieter operation and better dehumidification.
Heat Pumps – Heat pumps both heat and cool homes. In the winter, the heat pump removes heat from the heat exchanger and pumps it into the indoor air delivery system. In the summer, the process is reversed, and the heat pump moves heat from the indoor air into the heat exchanger. The heat removed from the indoor air during the summer can also be used to heat water, providing a free source of water heating.
Top-Rated Products
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Allegiance 18Two compressors for two stages of cooling Ultra high efficiency, up to 18.90 SEER rating, attractive |
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Before you buy... Interior Doors
Interior doors should be selected for their resource conservation value in addition to aesthetics and economic value. No longer is it necessary to hang solid wood doors created from old-growth trees. Other more efficient options are available to consumers.
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