According to the different energy sources utilized by heat pumps, heat pumps can be classified as follows.
I. Air source heat pump
Using air as the "source", air source heat pump, through the role of refrigerant, energy transfer. The current products are mainly domestic heat pump air conditioners, commercial unit-type heat pump air conditioning units and heat pump hot and cold water units. Heat pump air conditioners have accounted for 40-50% of sales of household air conditioners, with an annual output of more than 4 million units. Heat pump hot and cold water units since the early 1990s, in the hot summer and cold winter areas have been widely used, according to incomplete statistics, some cities in the region central air conditioning heat and cold sources using heat pump hot and cold water units have accounted for 20-30%, and the application continues to expand and has the trend of moving to this.
Second, the water source heat pump
Groundwater as a hot and cold "source", the use of heat pumps in winter to absorb its heat to the building heating, heat pumps in the summer will absorb the heat to its discharge, to achieve the cooling of the building. Although the current air energy heat pump unit has a wide range of applications in China, but it has a heat pump heat supply with the outdoor temperature decreases and frost problems, while the water source heat pump to overcome the above shortcomings, and high operational reliability, in recent years, the domestic application of the trend of gradual expansion.
Third, ground source heat pump
Ground-source heat pump is a technology that uses the earth as a heat source to air condition the building. In winter, the heat pump raises the low-level heat energy in the earth to heat the building, while storing cold for summer use; in summer, the heat pump transfers heat from the building to the ground to cool the building, while storing heat for winter use. Because of its energy saving, environmental protection and thermal stability, it has attracted the attention of countries all over the world. Europe, America and other developed countries have been utilizing ground source heat pumps for decades, especially for heating, and have accumulated a lot of information and data on design, construction and operation.
Fourth, the composite heat pump
In order to make up for the limitations of a single heat source heat pump and make full use of low-level energy, a variety of composite heat pumps are used. Such as air - air heat pump unit, air - water heat pump unit, water - water heat pump unit, water - air heat pump unit, sun - air source heat pump system, air back heat pump, sun - water source heat pump system, thermoelectric water triplex composite heat pump, soil - water source heat pump system, etc.
1、Sun-air heat source heat pump system
The solar-air heat source heat pump system is a newly developed system based on the traditional air heat source heat pump system, using solar heat source. It can cool, heat, and supply domestic hot water, and is a new type of cooling and heat source system using natural energy, no pollution, wide applicability and high efficiency.
2、Soil-water heat pump system
Soil - water heat pump (hereinafter referred to as soil heat pump) can use low-grade soil heat to provide hot water or heating to buildings. The United States, Germany and Sweden and other Nordic countries, there are tens of thousands of such heat pump devices in operation, soil heat pump technology has become mature, and quickly to promote the use. Currently being developed soil heat pump for heating technical specifications.
3, solar - water source heat pump air conditioning system
Solar water source heat pump system consists of three parts, namely, solar collector system, water source heat pump system and hot water supply system. Its system is the building's fire pool as a water storage supply system. to solve the intermittent and unstable nature of solar energy. When the loop water temperature is higher than 35℃, the water source heat pump air conditioning system is disconnected from the fire fighting pool and the cooling tower is put into operation. When the loop water temperature is between 15~35℃, the solar energy stops running as the cooling tower and the solar energy collected from the heat source of domestic hot water supply is used to heat domestic water; when the loop water temperature is lower than 15℃, the loop is connected to the fire fighting pool and the solar water source heat pump air conditioning system absorbs solar energy. If there is still excess solar energy, it can continue to heat domestic water.