1 Introduction According to statistics, by the end of 2000, the national annual construction area will be 36 billion square meters, of which 7.3 billion square meters of urban areas are mostly residential buildings. With the continuous improvement of people's living standards and the ever-increasing demands on the comfort of living, Particularly in the northern areas, heating in winter and cooling in the summer have become necessary tools for improving the living environment. Especially with the further improvement of housing loans and other policies, the size of individual buyers will continue to increase. A series of mid- to high-end residential buildings suitable for middle and high-income families are emerging, including many luxurious villas. More than 100 square meters of residential new homes in the proportion is also growing. In this type of residential, equipped with heating and air conditioning equipment is also a basic requirement. As a real estate developer, to such high-end residential with heating equipment and air-conditioning equipment, the initial investment in the total cost of the proportion is not high, but it can greatly enhance the grade of residential, so from the above analysis we can see that residential The heating and air conditioning industry not only has a bright future in the market but also has many articles to make. This article compares the different ways of cooling and heating in the residential quarters in the north area and puts forward the hot and cold co-supply mode based on the water source heat pump machine according to the actual situation in our country. This is the most practical and feasible way on the market at present A trend of future development. 2 Northern District Heating and Cooling Mode With the continuous improvement of people's living standards, the rapid development of residential air conditioning, split air conditioners currently on the market also mainstream, but with the development of science and technology, new residential air-conditioning continue to emerge, such as a Drag multi-split air-conditioning systems, VRV / MRV air-conditioning systems, air source / water source heat pump hot and cold water air-conditioning systems, lithium bromide absorption of hot and cold air conditioning systems and so on. In northern China, residential heating in winter is one of the prerequisites for people's lives. In the past, the main methods of residential heating were centralized coal-fired heating (regional boilers and cogeneration) and coal-fired decentralized heating (small boilers and domestic heating boilers). In recent years, with the advancement of technology and improvement of living standards, new and different heating and cooling systems have gradually entered the family. In our country, especially in recent years, the household hot and cold source integrated machine developed rapidly, according to the delivery of cold medium, can be divided into the following three types: (1) R22 direct pipeline expansion system, such as Japan VRV system, Haier MRV system, the United States MDV system, split wall machine, Guiji, etc .; (2) duct system, air duct system to air as the transmission medium, the principle and the large air system The principle is basically the same. It uses the outdoor unit to generate heat and / or heat in a concentrated manner, to cool / heat the indoor air or return air and fresh air, and then sent to the room. (3) Cold / hot water unit, cold / hot water unit The medium is usually water or glycol solution. It produces cold / hot water through the outdoor unit and is delivered by the piping system to the indoor end unit, where it exchanges heat with the indoor air. The system's indoor end unit is usually a fan coil. The three systems, each with its own advantages and disadvantages, have different degrees of development depending on their national conditions. They mainly develop "fluorine system" air conditioners in Japan, while the "wind system" in the United States is more rapidly developed. According to China's national conditions, which kind of air-conditioning system is the direction of our future development. On this issue, several teachers at Tsinghua University in the "Refrigeration and Air Conditioning" magazine published an article entitled "Domestic small central air conditioning industry status quo analysis and outlook" article, the article on the above issues are very detailed analysis. They think that from a technical maturity perspective, the national level of economic development, combined with the structure of the building and other factors should be considered in the development of cold / hot water units. Practice shows that indeed. Cold / hot water unit according to its heat medium, water / water heat pump (water source heat pump), wind / water heat pump (air source heat pump), lithium bromide absorption chiller units of three types. 2.1 Direct Combustion Lithium Bromide Chiller This heating method uses lithium bromide absorption chiller for heating. In summer, the chiller generates chilled water with a temperature of 7/12 ° C (water temperature / return water temperature) to meet the needs of building air conditioning. In winter Chiller to provide 60 ~ 80 ℃ water temperature for heating. When needed, hot water can be supplied throughout the year (60 ℃) Lithium bromide absorption chillers can be divided into direct-fired, steam-type and hot-water type. At present, the hot water type lithium bromide absorption chiller that uses solar energy for refrigeration is still in the stage of experimental research. Due to the instability and intermittence of solar energy and the fact that solar collectors on the market can not match the chiller and the cost problems Seriously hindered the promotion of this energy-saving refrigerator. When the local power shortage, there are heating power plants or have enough heating boilers in winter, especially waste heat, waste heat available, lithium bromide absorption chiller should be preferred; but when the local supply of natural gas at low cost, while technical and economic More reasonable, because direct-fired combustion engine than other types of absorption chiller, with high thermal efficiency, less fuel consumption, safety, and can be a dual-use features, should be preferred. Direct combustion lithium-bromide hot and cold water unit heating and cooling, from the environmental protection, energy utilization, operating costs and overall cost, compared with cogeneration mode heating, are not dominant, but because it is cold, heat source integration In a district with air conditioning requirements can be considered. 2.2 Air source heat pump Air source heat pump in the summer to do the refrigeration cycle, the room waste heat and the unit's input power are transferred to the outdoor air, in order to achieve the purpose of cooling the room; in winter to do the heating cycle, extract heat from the outdoor air Together with the unit input power transferred to the room, in order to achieve the purpose of warming the room. When operating in cooling mode, its energy efficiency ratio (EER) is higher than 3.0, its coefficient of performance (COP) value is above 3.0 during heating operation, so its power consumption is only 25% -50% , And a dual-use, improve the utilization of equipment. However, when the outdoor temperature is lower than -5 ℃, the heat supply is reduced, the energy saving benefit is reduced, and the problems of unit failure, room temperature easy to change and the like are caused. 2.3 Water source heat pump Water source heat pump compared with the air source heat pump, because of the improvement and stability of its working conditions, not only improve the efficiency of the unit, and stable and reliable operation; there is no frosting, prolong the service life. The EER value, COP value is as high as 4.3 ~ 4.6. Power consumption is only 60 ~ 70% of the wind source heat pump machine; also has heat recovery, energy-saving benefits significantly, so water source heat pump is to solve the northern city of building heating and air conditioning the best solution. Water source heat pump according to its heat medium to points, water / air heat pump and water / water heat pump points; water source heat pump if the use of earth (soil, groundwater, groundwater) as a heat source, also known as ground source heat pump. Ground source heat pump is a low heat source for the heat pump air conditioning system, ground source heat pump with environmental protection, energy saving, good thermal stability, etc., the market prospects are very good. However, due to the ground source heat pump equipment (such as land heat exchanger, pipe) and process equipment and other issues are not yet complete, the current application is still in the theoretical stage of exploration. Water source heat pump machine and room air conditioner price quite, as long as the water source to solve the problem of heat, air conditioners will be a strong contender room. 3 Modes of New Cold / Hot Water Supply Air-source heat pump cold / hot water units are widely used in the areas of the Yangtze River, the South of the Yangtze River and the Yellow River Basin in China. The technologies are also very mature. In our country, the northeast, north and northwest , Inner Mongolia and other regions of the application is more rare in these cold areas can also use air-source heat pump cold / hot water unit to heating and cooling it? Cooling, no doubt yes, then heating how? Some professors such as Harbin Institute of Technology, Ma Liang and others think that air-source heat pump chillers can not operate normally in the coldest part of the northern part of the world because the compression ratio of the units is greater than 10 or even more than 20 at run-time. Therefore, Professor Ma proposed the use of air-source heat pump hot and cold water units and water source heat pump running a joint solution to this contradiction, this time, the system's COP value can reach about 2.0. However, due to its high cost, it will hinder the system's promotion and use. I believe that it would be better to use the city's heating pipe network for the article, with cogeneration heat, waste heat + water source heat pump chiller + fan coil mode more convenient and effective. In the district to set up a thermal station, equipped with water / water heat exchanger, cooling tower. The heat exchanger is used for heating operation of a normal-temperature water-cooled water source heat pump cold / hot water unit at a temperature of 20 ° C to 25 ° C generated by heat exchange with cogeneration waste heat and waste heat so as to ensure that the water temperature at a low pressure is constant. The cooling tower is used to ensure that the water source heat pump for high-pressure cooling water temperature measurement is constant, and heat pump can also provide users with hot water, naturally omitted the costly domestic hot water pipe network. In summary, I believe that in the northern part of a district on the planning and construction, this one machine, but also with environmental protection, energy-saving hot and cold co-mode should be vigorously promoted. Of course, in the south, because of its soil superiority, ground source heat pumps should be vigorously promoted. 4 heat cogeneration waste heat, waste heat + water source heat pump machine + fan coil hot and cold co-mode features 4.1 Cogeneration waste heat, waste heat utilization At present, the large and medium-sized cities in northern China are based on combined heat and power, regional boiler room as a heat source The central heating method, and is based on the way of thermal power. High-temperature and high-pressure steam coming out from the thermal power plant is subjected to two to three heat transfer processes to generate 85 to 95 ° C heating hot water and generate 50 to 60 ° C domestic hot water at the same time, which are respectively sent to two different heat pipe networks Into millions of households. At present, the average power generation efficiency of large-scale thermal power plants in our country is 33%, while the power generation efficiency when heating power plants is 20%, and over 70% of the remaining 80% of the heat can be used for heating. The cogeneration waste heat, the use of waste heat will greatly improve the thermal power plant power generation efficiency, and water source heat pump machine is doing the heating operation, low pressure measurement of water temperature is only normal temperature, so there is no need to set the multi-stage heat station, the temperature of water delivery Not high (30 ~ 40 ℃), so not only to reduce the heat station and pipe network investment, but also reduce the energy loss, associated with the water treatment equipment is also reduced, serve multiple purposes. 4.2 Water source heat pump system Water source heat pump system has been done in the front of a simple overview, where we compare with other systems to again look at its advantages and disadvantages 4.2.1 water source heat pump system and civilian split air-conditioning Table 1 No. water source Heat pump system Civil split air conditioners 1 Large energy efficiency (4.3 ~ 4.6), low energy-saving efficiency (3.0), no energy saving 2 Wide air blowing area, uniform cooling capacity, easy to decorate a single air volume, uneven cooling, unfavorable room decoration 3 Can provide heat recovery and provide domestic hot water can not provide domestic hot water 4 does not damage the appearance of the building, not the formation of the environment Heat island effect will destroy the appearance of the building, will form a heat island effect 5 host integration, refrigerant leak, easy to disassemble, Inside and outside the machine separate from the installation of a greater impact, easy to leak 6 to facilitate the introduction of fresh air can not lead the fresh air 4.2.2 water source heat pump system and lithium bromide absorption chiller system comparison Table 2 No. water source heat pump system central air conditioning and heating system 1 The use of water at room temperature, you can make full use of waste heat, waste heat using steam or hot water, can not make full use of waste heat, waste 2 do not have to set up a large central host room, saving floor space, no need to manage someone Dedicated computer room, hand management 3 can be divided into household metering, reasonable, convenient inconvenient to measure, charging unreasonable 4 initial investment is small, easy to expand initial investment, Not easy to expand 5 energy efficiency, energy saving but not necessarily energy-saving 6 system is simple, low maintenance costs system complexity, high maintenance costs 4.2.3 initial investment comparison (unit yuan / m2) Table 3 hot and cold supply heating / Cooling Total Remarks Public building Internal cogeneration Central heating + splitter 60 * 220 * 280 Separating machine Combined heat and power heat pump 60 * 150 * 210 Direct combustion engine 168 80 * 248 Note: * "Data from" Analysis and Comparison of Different Heating Modes "As can be seen from the table, the investment in the mode of water source heat pump is the most economical in the mode of hot and cold water supply. 4.2.4 Comparison of Operating Costs (Unit: RMB / m2 · year) Table 4 Co-generation and cooling modes Heating and Cooling Total Cogeneration Heat + splitter 12.6 * 15.3 27.9 Cogeneration waste heat + water source heat pump 9.0 * 13.8 22.8 Direct Combustion Engine 14.3 * 16.9 31.2 Note: Data with "*" are taken from "Analysis and Comparison of Different Heating Modes" As can be seen from the table, using water source heat pump for hot and cold co-mode, Under, its annual operating costs are the lowest. 5 Conclusion For the planning of cold and heat source for the community, according to the actual situation can be used for different programs. In areas with adequate gas supply, priority should be given to direct combustion engines. Where sufficient electricity is available, water source heat pumps should be used. And should make full use of the northern part of the cogeneration heat, waste heat on the district hot and cold supply. This greatly improves the power plant thermal efficiency, but also reduce the heat station and pipe network investment, as well as pipe network energy transmission losses. References 1 Li Xianrui. China Construction Information Heating and Cooling, 2001,4: 4 ~ 7 2 Wu Deqian. China Construction Information Heating and Cooling, 2001,4: 10 ~ 11 3 Jiang Yi, Di Hongfa, Liu Zhaohui. China Construction Information heating and cooling, 2001, 4: 12 ~ 14 4 Fang Zhaohong, Diao Niren, Su Dechao. China Construction Information Heating and Cooling, 2001,4: 62 ~ 64 5 Zhao Shihuai, Huang Xiaodong. Fujian 2001 Annual Conference Materials, 2001 , 10: 1 ~ 5 6 Wang Zijiu. HVAC, 1999,6 (29): 35 ~ 38 7 Chen Yanhua, Qi Chuanbin. HVAC, 2001,4 (31): 29 ~ 32 8 Liu Guodan, Yu Hui Li, Hu Songtao, etc. HVAC, 2001, 4 (31): 1 ~ 3 9 Ma Liangliang, Yang Ziqiang, Yao Yang, etc. HVAC, 2001,3 (31): 28 ~ 31