释义 |
Heating/cooling systems Heating/cooling systemsMethods for the delivery of hot or cold air depend on the type of unit served and distribution system. For example, forced air is used for heated air systems, whereas for fluid and electrical systems, convection and radiation are used to transfer heat. Central heating systems use a furnace, boiler, or heat pump to transfer heated air, water, or steam through ductwork or radiators. For smaller environments and/or temporary circumstances, heating may also be provided via local, nonmechanical means, such as electric space heaters, baseboard and wall heaters, heat pumps, and passive systems such as green roofs and natural ventilation.boilersUsed to heat water for domestic use and hydronic heating systems. Similar to furnaces, boilers also run on a variety of energy resources, including electric and biomass.central heating systemsUsed in mass dwellings in cold climates to simultaneously distribute a treated hot/cold, air/fluid to multiple spaces. Central systems use a furnace, boiler, or heat pump to transfer heated air, water, or steam through ductwork or radiators. For smaller environments and/or temporary circumstances, heating may also be provided via local, nonmechanical means, such as electric space heaters, baseboard and wall heaters, heat pumps, and passive systems.electric space heaters, baseboard, and wall heatersUnits for small spaces with local heating requirements do not require a comprehensive duct-work or piping. Wall heaters are installed on the exterior wall; baseboard heaters are installed at the bottom of any interior wall; and space heaters are portable.furnacesUsed to heat air only. These devices operate efficiently and can use a wide range of energy resources, such as natural gas, propane, biomass, fossil oil, or electricity.green roofsA natural heating/cooling alternative that provides thermal insulation and evaporative cooling due to water circulating from plants.heat pumpsUsed to heat air and water for both heating and cooling. These systems collect heat from a variety of sources including air, water, or specialized liquids and circulate the substance through pipes. Air-based heat pumps are used when cooling a structure, and ground-based pumps are used when heating one. Both use electricity to pump the air or liquid and to operate the compressor. |