在选择和安装地热泵时, 考虑加热和冷却效率, 系统的经济学, 以及你网站的特点. 一定要找到一个合格的安装程序.
The heating efficiency of ground-source and water-source heat pumps is indicated by their coefficient of performance (COP), 提供热量的单位是Btu / Btu. 它们的冷却效率用能效比(EER)来表示。, which is the ratio of the heat removed (in Btu per hour) to the electricity required (in watts) to run the unit.
寻找能源之星®标签，这表明该设备符合能源之星标准. Manufacturers of high-efficiency geothermal heat pumps (GHPs) voluntarily use the EPA ENERGY STAR label on qualifying equipment and related product literature. 许多ghp携带美国.S. 能源部(DOE)和环境保护局(EPA)的“能源之星”标签.
Although the purchase and installation cost of a residential GHP system is often higher than that of other heating and cooling systems, properly sized and installed GHPs deliver more energy per unit consumed than conventional systems. For further savings, GHPs equipped with a device called a "desuperheater" can heat household water. 在夏季降温期间, 从房子里带走的热量被用来免费加热水. 在冬季，水暖成本降低了一半左右.
这取决于气候等因素, 土壤条件, 您选择的系统特性, 你可以在2到10年内通过较低的水电费收回你的初始投资. And -- when included in a mortgage -- your investment in a GHP will produce a positive cash flow from the beginning. 例如, 如果额外的3美元,500美元的GHP费用将增加每月30美元的按揭付款, the energy cost savings will easily exceed that added mortgage amount over the course of each year.
在改造, GHP的高效率通常意味着更低的水电费, 允许投资在2到10年内收回. It may also be possible to include the purchase of a GHP system in an "energy-efficient mortgage" that would cover this and other energy-saving improvements to the home. 银行和抵押公司可以提供更多关于这些贷款的信息.
联邦政府可能会有特别的规定或激励措施, 状态, and local governments; power providers; and banks or mortgage companies that offer mortgage loans for energy-saving home improvements. Be sure the system you're interested in qualifies for available incentives before you make your final purchase.
在美国，浅层地温相对来说是恒定的, 因此，地热热泵(GHPs)几乎可以在任何地方有效地使用. 然而, 特定的地质, 水文, and spatial characteristics of your land will help your local system supplier/installer determine the best type of ground loop for your site.
Factors such as the composition and properties of your soil and rock (which can affect heat transfer rates) require consideration when designing a ground loop. 例如, soil with good heat transfer properties requires less piping to gather a certain amount of heat than soil with poor heat transfer properties. The amount of soil available contributes to system design as well -- system suppliers in areas with extensive hard rock or soil too shallow to trench may install vertical ground loops instead of horizontal loops.
Ground or surface water availability also plays a part in deciding what type of ground loop to use. 这取决于深度等因素, 体积, 和水的质量, 地表水可以作为开环系统的水源, 或者在一个闭环系统中作为管道线圈的储存库. 地下水也可以作为开环系统的水源, 水质适宜，地下水排放符合各项规定.
在你购买开环系统之前, 确保你的系统供应商/安装人员已经充分调查了你的站点的水文情况, so you can avoid potential problems such as aquifer depletion and groundwater contamination. Antifreeze fluids circulated through closed-loop systems generally pose little to no environmental hazard.
土地的数量和布局, 你的风景, and the location of underground utilities or sprinkler systems also contribute to your system design. Horizontal ground loops (generally the most economical) are typically used for newly constructed buildings with sufficient land. Vertical installations or more compact horizontal "Slinky™" installations are often used for existing buildings because they minimize the disturbance to the landscape.
正确安装管道需要专业的技术知识和设备, 所以一个GHP系统的安装不是一个自己动手的项目. 找到一个合格的安装程序, 联系当地的公用事业公司, 国际地源热泵协会, or the Geothermal 热泵 Consortium for their listings of qualified installers in your area. 安装人员应该有证书和经验. 向拥有几年历史的系统的所有者询问推荐信，并对其进行检查.
地埋管换热器是由封闭或开环管道系统组成. 最常见的是闭环, in which high density polyethylene pipe is buried horizontally at 4 to 6 feet deep or vertically at 100 to 400 feet deep. These pipes are filled with an environmentally friendly antifreeze/water solution that acts as a heat exchanger. In the winter, the fluid in the pipes extracts heat from the earth and carries it into the building. 在夏天, 系统反过来从建筑中吸收热量并将其储存到较冷的地面上.
The air delivery ductwork distributes the heated or cooled air through the house's ductwork, 就像传统系统一样. The box that contains the indoor coil and fan is sometimes called the air handler because it moves house air through the heat pump for heating or cooling. The air handler contains a large blower and a filter just like conventional air conditioners.
Most geothermal heat pumps are automatically covered under your homeowner's insurance policy. 联系你的保险公司确认一下. 即使你的供应商会为你的系统买单, 最好以书面形式告知他们你拥有一个新系统.
The biggest benefit of GHPs is that they use 25% to 50% less electricity than conventional heating or cooling systems. This translates into a GHP using one unit of electricity to move three units of heat from the earth. 根据环保署的说法, geothermal heat pumps can reduce energy consumption -- and corresponding emissions -- up to 44% compared with air-source heat pumps and up to 72% compared with electric resistance heating with standard air-conditioning equipment. GHPs还通过保持大约50%的室内相对湿度来改善湿度控制, 使GHPs在潮湿地区非常有效.
Geothermal heat pump systems allow for design flexibility and can be installed in both new and retrofit situations. 因为硬件需要的空间比传统的暖通空调系统更少, 可以大幅度缩小机房规模, 为生产用途腾出空间. GHP系统还提供了优秀的“区域”空间调节, 让你家里的不同部分可以加热或冷却到不同的温度.
GHP systems have relatively few moving parts and those parts are sheltered inside a building, 因此，这些系统是耐用和高度可靠的. 地下管道的保修期通常为25至50年, 而热泵通常可以使用20年甚至更长时间. 它们通常没有室外压缩机，所以ghp不容易受到破坏. 除了, 生活空间的组成部分很容易接近, which increases the convenience factor and helps ensure that the upkeep is done on a timely basis.
ghp没有像空调一样的外部冷凝装置, 所以不用担心外面的噪音. A two-speed GHP system is so quiet inside a house that users usually do not know it is operating.