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We all have a common sense: it is impossible for water to spontaneously flow from a low position to a high position. In order to transport water from the low position to the high position, a water pump (consuming electric energy as compensation) must be used to transport water from the low position to the high position. Similarly, heat cannot be spontaneously transferred from a low temperature environment to a high temperature environment. To transfer heat energy from low temperature environment to high temperature environment, it must pass through a device and consume a part of mechanical work (such as electric energy) as compensation. This device is called a "heat pump". Therefore, the working principle of Yi Tong air-cooled heat pump hot water unit is to drive the compressor to run by inputting a small amount of electric energy, and the whole heat pump system is put into operation, continuously absorbing heat from the low-temperature environment through the evaporator, and transferring the heat absorbed by the system and the consumed electric energy to the high-temperature environment through the condenser. The principle is as follows. Every time the compressor consumes 1 part of electric energy, the working medium can transport 2 ~ 6 parts of heat energy (depending on the ambient temperature). Traditional electric, oil and gas water heaters are essentially energy conversion devices, which convert the chemical energy of electricity and fuel into heat energy. For example, in a gas water heater, combustion of gas under the action of oxygen will lose heat energy such as incomplete combustion, high-temperature heat loss and heat exchange loss, and the actual heating coefficient is between 0.5 and 0.7. The electric energy consumed by heat pump is only supplied to machinery (compressor, motor, etc.). ) A system that does work and carries heat energy-transfers heat energy from a low-level (low-temperature) heat source to a high-level (high-temperature) heat source. Therefore, it is not a thermal energy conversion device, but a thermal energy processing device, which is not limited by the thermal energy conversion efficiency (the limit is 100%). Overview of Heat Pump Technology 1.2 The development and application of heat pumps originated in Europe and America, and China is the largest market. /kloc-At the beginning of the 9th century, the British physicist J.P.Joule put forward the principle of changing the temperature of the compressed fluid by changing its pressure. 1854, W.Thomson (william thomson) published a paper, put forward the concept of heat multiplier and described the idea of heat pump for the first time. 19 12 Zurich, Switzerland successfully installed a set of heat pump equipment with river water as low heat energy-this is the first water source heat pump system in the world. The following decades are the research and development stage of heat pump, and its development lags behind the development of air conditioning for a long time. 1973 the global energy crisis has made people pay attention to energy conservation and recycling, which has accelerated the development of heat pumps in the world. Large-scale commercial applications have been in the past 20 years. Take the developed country USA as an example. In 1985, there were14,000 heat pumps in use, and in 1997, 45,000 were newly installed. By 2004, 400,000 heat pumps had been installed, with a steady growth rate of 65,438+00% every year. In China, the heat pump industry only started in recent years. There were imported products and joint venture products in 200 1 and 2002, and the development momentum was very strong. With the improvement of people's awareness of energy conservation and environmental protection-that is, people can calculate the fuel cost saved by using heat pump products for one or two years, and the cost of investment equipment can be recovered. Therefore, in the near future (2 ~ 3 years), heat pump water heaters will surely "fly into the homes of ordinary people" and become the mainstream of the water heater market. According to experts' conservative estimation, there will be 30 billion yuan business opportunities in China heat pump market in the next three years. 1.3 main performance characteristics 1.3. 1 high efficiency and energy saving According to the working principle, the heat pump unit can obtain a lot of free heat from the surrounding air. Generally speaking, for every 1 kwh of electricity consumed, 3 ~ 4 kwh of electricity can be generated. The unit energy efficiency ratio (COP) can reach above 3 ~ 4 on average, which is equivalent to thermal efficiency above 300% ~ 400%, and energy saving above 67 ~ 75% compared with direct electric heating. The operating costs are 1/4 for ordinary electric water heaters, 1/3 for gas water heaters, 1/2.5 for oil water heaters and1/0/.5 for solar water heaters. 1.3.2 is economical and durable. Because of its high efficiency and low operating cost, it is less than 1/3 ~ 1/4 of the electric boiler, which can greatly reduce the power supply load and save the power capacity fee. Compared with gas-fired and oil-fired boilers, there is no need for a corresponding fuel supply system, so there is no need for fuel transportation costs and management costs. The equipment is compact, easy to operate and maintain, and no manual management fee is needed. The unit is installed outdoors, such as podium or roof, outdoor balcony, etc. And there is no need to set up a special equipment room, which does not occupy effective building area and saves civil engineering investment. The compressor, heat exchanger and main components are all famous brand products, which have reliable operation and long service life. The shell is made of mirror stainless steel, which is elegant and beautiful, durable and not easy to rust. 1.3.3 The safety and environmental protection heat pump unit has no pollution to the atmosphere and environment, and the energy saving effect is obvious. It belongs to environmental protection products and conforms to the current basic policies of energy and environmental protection in China. The heat pump unit has various automatic safety protection functions, such as high and low pressure abnormal protection, compressor overload protection, fan overheating protection, phase failure protection, leakage protection, sensor fault protection, temperature limit protection and so on. Compared with the traditional hot water boiler, there is no corresponding fuel supply and smoke exhaust system, and the system is safe, hygienic and clean, and there are no potential safety hazards such as fuel leakage, fire and explosion. Compared with the traditional piston compression heat pump unit, Yi Tong heat pump adopts scroll compressor, which has low noise and will not adversely affect the surrounding environment. 1.3.4 The working performance of the air-source heat pump hot water unit with strong adaptability changes obviously with the outdoor climate. When the outdoor ambient temperature is in the range of 0 ~ 40℃, the heat pump unit can work normally. The heat pump unit can provide hot water above 60℃, which fully meets the needs of sanitary hot water, swimming pool constant temperature, heating and so on. With the use of water tank, make full use of the preferential electricity price at night for heating, and reserve a large amount of hot water in advance. Multiple water heaters can be connected in parallel to meet more hot water demand. In addition, in the season when the demand for hot water decreases or when maintenance is needed, some units can be stopped without affecting the operation of other units. Chapter II Comparative Analysis of Energy Consumption 2. 1 Analysis of Operating Cost 2. 1 Thermal Efficiency and Calculation Method of Effective Calorific Value of Various Equipment Output Energy Types Effective Calorific Value Electric Heating Calorific Value (860kcal/ kWh) × Thermal Efficiency (95%) 8 17kcal/ Diesel Calorific Value (10200 kcal) Suppose the consumption of hot water in our factory is 50 tons. In the same case, 50 tons 15℃ cold water is heated to 55℃ hot water, and the water temperature is increased by 40℃. Heat demand: 50,000 liters × 1kcal/ liter ℃× 40℃ = 2,000,000 kcal, then the operating expenses of various heating equipment are as follows: electric heating 2,000,000 kcal17 kcal/degree = 2,448 degrees× 1 degree. ㎏=26 1㎏26 1㎏×6.5 yuan ㎏= 1697 Yuan LPG 20000000 kcal ㎏ 3440 kcal/㎏ 9600 kcal/. Degree =58 1 yuan 2. 1.3 Comparison of the use cost and cost saving of various heating equipment; The daily cost of energy types is average; Save the cost per person per day; Using heat pump saves 2448 yuan per year; Using heat pump can save 893,520 yuan 1867 yuan 68 1455 yuan diesel oil 16 per year. 97 yuan 6 19405 yuan16 yuan 407340 yuan liquefied gas 1456 yuan 546040 yuan 875 yuan 3 19375 yuan solar energy 88 1 yuan 321yuan. Heat pump unit 58 1 yuan 2 12065 yuan Note: ① Electricity fee 1 yuan/kwh, diesel 6.5 yuan/㎏, liquefied gas 7 yuan/㎏ ② Solar energy is used in rainy days every year 120 days, and the cost of auxiliary heating equipment is different. The above is the annual average daily cost, that is, according to. 2.2 Comparative advantages of heat pump and various heating equipment 2.2. 1 What are the advantages of heat pump compared with conventional solar products? The product has a wide application range, and the applicable temperature range of the product is-10 ~ 40℃, which can be used all year round, and is not affected by bad weather such as rainy and snowy weather and winter nights, and can be used normally. It can be heated continuously. Compared with the traditional solar water storage, heat pump products can continuously heat and supply water to meet the needs of users. Low operating cost: Compared with conventional solar energy, the operating cost is higher than that of solar energy in sunny days in spring, summer and autumn, but the thermal efficiency is much higher than that of solar-assisted heating in rainy days and at night. On average, the annual energy consumption of conventional solar auxiliary systems is much higher than the total energy consumption of products. Convenient installation: the air source heat pump occupies a small space, which is similar to the outdoor unit of air conditioner. It can be directly connected to heat preservation water tank or heating pipe network, and is suitable for high-rise buildings in large and medium-sized cities. Heat pump products are the best choice for local central heating. 2.2.2 What are the advantages of heat pump products compared with boilers? High thermal efficiency: the annual average thermal efficiency of products is above 300%, while the thermal efficiency of boilers will not exceed 100%. Low operating cost: compared with oil-fired and gas-fired boilers, the annual average energy saving is 70%. In addition, due to the reduction of electricity price and the increase of fuel price, the advantages of operating costs are increasingly prominent. Environmental protection: the heat pump product has no combustion emission, and the refrigerant is R4 17A, which has no pollution to the ozone layer and is a good environmental protection product. Safe operation, no need to be on duty: compared with oil-fired boilers, the operation is absolutely safe, fully automatic, no need to be on duty, which can save personnel costs. Modular installation, easy to add equipment: the product is installed in parallel with multiple units, and equipment can be added at any time when the user's water consumption increases. 2.2.3 What are the advantages of heat pump products compared with liquefied gas? Safe. There were no accidents such as air leakage, poisoning and explosion. Easy to use. When you want to use hot water, you just need to turn on the tap. There is no liquefied gas, so every time you use water, you should open and close the valve, take air regularly and check the battery regularly. Save money. The average thermal efficiency of heat pump is above 300%, while that of liquefied gas is only 75%. According to the cost calculation, the cost of using heat pump is only 1/3 of that of liquefied gas. For a while, I used electricity to soak hot springs at home-this is an advertisement about heat pump water heaters made by Midea on Phoenix Satellite TV, which mainly reflects its energy-saving advantages. Many people know the basic principle of heat pump. In the evaporator, the refrigerant absorbs 3 parts of heat in the air, the compressor consumes 1 part of electric energy to do work to raise the temperature of the refrigerant, and then the heat exchanger transfers 4 parts of heat to the water. Finally, the refrigerant is decompressed and cooled by the expansion valve, and then enters the evaporator for the next cycle. (Water only passes through the heat exchanger, and then flows into the heat preservation water tank for standby. Therefore, judging the quality of a heat pump water heater product mainly depends on the following aspects: 1. Because the refrigerant enters the evaporator at low temperature, the evaporator is prone to frost at low ambient temperature, which will affect the heat absorption efficiency of the refrigerant. Many products have not solved this problem well, so when the temperature is low, the products can hardly be used. The solution is to control the heat exchange efficiency of refrigerant in the heat exchanger by intelligent program when the evaporator frosts, so that the refrigerant can return to the evaporator at a higher temperature, thus defrosting. Some products can also defrost, but they cannot control the heat exchange efficiency of refrigerants. Instead, the high-temperature refrigerant directly comes out of the compressor and directly enters the evaporator for defrosting without passing through the heat exchanger. In this case, the temperature difference will be great when defrosting, which is easy to cause the rupture of the evaporator copper tube, thus affecting the evaporator life; 2. The quality of compressor is also a key. Generally, powerful manufacturers will choose American grain scroll compressor, and Panasonic compressor can also be accepted at home. 3. The efficiency of heat exchanger is also a key factor. At present, the heat exchanger used in the United States is a V-shaped heat exchanger with three rows of copper tubes (generally only two rows of copper tubes). At present, some products on the market directly insert the copper tube through which the high-temperature refrigerant passes into the water tank for heat exchange. Because the water in the water tank rarely flows, this will lead to scaling of copper pipes and reduce the heat exchange efficiency. What's more serious is that the copper tube is easy to break, which will cause the refrigerant to leak into the water, which is very harmful to the health (many brands do this). So I suggest that you don't be greedy and buy low-priced products. Because of the low cost, the quality of some accessories will not be very good. Besides recommending beauty cosmetics, I also recommend a brand: Yi Tong. Yi Tong's heat pump is also well done, which is different from Midea's style: Yi Tong pays attention to technology, Midea pays attention to marketing, and has great support for agents. There are many brands looking for our agents. In the end, I only choose two: Midea and Yi Tong. Although their products are more expensive, they are comfortable to make and have no worries. Some companies just make low-quality and low-priced products, which are easy to sell. However, after the sale, there are often problems, and some manufacturers can't solve them, so the boss has to close the door. Of course, you won't know if it's good until you use it, but I hope consumers will keep their eyes open when they buy it. I also hope that everyone can buy a heat pump with high cost performance, and I hope that the heat pump can be mass-produced as soon as possible, so as to reduce the cost and fly into thousands of households, so that everyone can soak electricity at home!