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　　Winter is coming, and many friends in the south are estimated to be inseparable from the company of air conditioning. Recently, some netizens who are familiar with the home appliance industry have summed up 10 cold knowledge about air-conditioning electric auxiliary heating. If you are afraid of cold, you may be able to learn it.However, with the development of the industry, commercial heating and cooling It will also bring us more and more consumer experiences, so that users can really feel the upgrade and change. https://puremind.com/product-category/puremind-air-conditioner/commercial-air-conditioner/

　　

　　1. 38≧: According to the standard, the air outlet temperature should reach above 38≧ when air conditioning is heating, which is higher than human body temperature, otherwise it will feel like cold air when blowing on people.

　　

　　2, wind speed: air conditioning heating, high wind speed when the outlet temperature is low, low wind speed when the outlet temperature is high.

　　

　　3. Temperature: After the air conditioner is turned on for heating, the air outlet temperature of 40≧ is faster than that of 60≧. Because the hot air floats up, the high temperature of the outlet air will float up to the roof faster, and the lower temperature will help the middle and lower air to heat up.

　　

　　Comprehensive 2 and 3, if the air conditioner wants to heat well, it needs to turn on the large air volume, and after turning it on, the air will be discharged at 40≧ first, and then the air will be heated to about 50≧ after the room temperature rises.

　　

　　4. The purpose of electric auxiliary heat: it is to heat the air outlet temperature. When the outdoor temperature decreases, the heating performance of the air conditioner will be attenuated. Turning on electric auxiliary heat can increase the air outlet temperature and avoid people feeling cold wind blowing.

　　

　　5. When do you need to turn on the auxiliary heating? According to the national standard, when the outdoor temperature is above 0≧, the auxiliary heating of air conditioner is turned off by default, and users can turn it on manually. When the temperature is lower than 0≧, it is turned on by default, and the user can turn it off manually.

　　

　　6. Principle of electric auxiliary heating: The electric auxiliary heating is at the lower end of the internal heat exchanger, in front of the air outlet of the air conditioner, with PTC ceramic heating rods inside and aluminum fins outside. After electric auxiliary heating, the temperature will reach 200~300≧, so electric auxiliary heating can’t be dry-burned, and the air conditioner must be blown after it is turned on.

　　

　　7. Will electric auxiliary heating blow white powder? The consultant learned that in 2024, the air-conditioning models were sold, and the sleeve pieces had been passivated, or Teflon coating was sprayed on the surface to prevent white powder blowing. At present, the models on sale will not have the problem of blowing white powder.

　　

　　8. When defrosting the air conditioner, can you turn on the electric auxiliary heat to avoid excessive cooling of the room?

　　

　　No way. When the air conditioner is defrosting, the internal fan stops running, and the air conditioner does not give out air. If the electric auxiliary heat is turned on, it will dry up and may burn out the internal machine parts. When the air conditioner is defrosting, it is not good for the internal machine to keep blowing air.

　　

　　9. Air conditioners that do not stop defrosting. When some models defrost, the internal heat exchanger will heat up. Is the electric auxiliary heating turned on?

　　

　　No, electric auxiliary heating can only heat the outlet air temperature, but not the heat exchanger.

　　

　　10. Japanese air conditioners are good at heating without electricity, but domestic air conditioners are not good at heating with electricity.

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　　The frequency of air conditioning is increasing.

　　

　　Hot summer day

　　

　　Is it advisable to stay in an air-conditioned room for a long time?

　　

　　Do I need to open the window to ventilate the air conditioner?

　　

　　The answer is coming ◎

　　

　　Turning on the air conditioner should not close the doors and windows.

　　

　　A set of experiments will show you.

　　

　　Many people have been in air-conditioned rooms for a long time.

　　

　　I will feel dizzy and sleepy.

　　

　　This may be that the indoor carbon dioxide concentration exceeds the standard.

　　

　　Experts said

　　

　　National standard of indoor carbon dioxide concentration

　　

　　The general requirement is below 1000ppm.

　　

　　For shopping malls, schools and other densely populated places

　　

　　Generally, the concentration of carbon dioxide is required to be below 1500ppm.

　　

　　When the indoor carbon dioxide concentration reaches 2000ppm

　　

　　The human body often feels dizzy and uncomfortable.

　　

　　There are only two or three people in the family.

　　

　　Why does the concentration of carbon dioxide exceed the standard?

　　

　　Two experimenters are in a 13-square-meter bedroom

　　

　　Close the doors and windows and turn on the air conditioner.

　　

　　By placing a good observer

　　

　　Real-time observation of indoor carbon dioxide concentration changes

　　

　　Over time

　　

　　The concentration of carbon dioxide keeps rising.

　　

　　Just half an hour.

　　

　　It has already exceeded 1500ppm.

　　

　　Experts said

　　

　　For the home environment

　　

　　This concentration has exceeded the standard

　　

　　after an hour

　　

　　The concentration of carbon dioxide in the air

　　

　　More than 2000ppm

　　

　　And it’s rising

　　

　　The experimenter opened the window for ventilation.

　　

　　After 15 minutes.

　　

　　Indoor carbon dioxide concentration

　　

　　Slowly dropped below 1000ppm.

　　

　　It can be seen that the doors and windows are closed and the air conditioner is turned on for 1 hour.

　　

　　It may cause the indoor carbon dioxide concentration to exceed the standard.

　　

　　If you sleep in this environment for one night,

　　

　　It is very likely that lack of oxygen will bring health risks.

　　

　　It is recommended to turn on the air conditioner.

　　

　　Open the window properly to get some air.

　　

　　For families that are inconvenient to open windows

　　

　　Consider purchasing a new fan.

　　

　　Instead of window ventilation

　　

　　Air-conditioned rooms should not stay long.

　　

　　Beware of “air conditioning disease”

　　

　　It is hot and hot in summer.

　　

　　Stay in an air-conditioned room for a long time

　　

　　Not only dizziness, headache

　　

　　It may also induce “air conditioning disease”

　　

　　Knowledge of small science popularization

　　

　　”Air-conditioning disease” is a series of diseases induced by long-term use of air conditioning. When using air conditioning, the space is relatively closed, the air is not circulating, pathogenic microorganisms are easy to breed, and the temperature difference between indoor and outdoor is large, so the body is not well adapted, so a series of symptoms will appear.

　　

　　Abdominal pain and diarrhea

　　

　　The stomach and intestines are very sensitive to the stimulation of temperature.

　　

　　Excessive indoor and outdoor temperature difference

　　

　　Accelerated gastrointestinal peristalsis

　　

　　Cause digestive dysfunction

　　

　　Cause abdominal pain and diarrhea

　　

　　catch a cold and have a fever

　　

　　Enter the room with low temperature from the hot outdoor.

　　

　　Easy to catch a cold and cough.

　　

　　Even induce asthma and pneumonia.

　　

　　Serious illness

　　

　　neck shoulder lumbocrural pain

　　

　　Thin clothes in summer

　　

　　Shoulder, knee, waist, etc.

　　

　　Exposed to the cool breeze for a long time

　　

　　It is easy to cause symptoms such as joint and muscle pain.

　　

　　It is easy to cause cervical spondylosis and scapulohumeral periarthritis.

　　

　　cardiac infarction

　　

　　From low temperature indoor to high temperature outdoor.

　　

　　Switch like this

　　

　　Will make blood vessels suddenly contract and expand.

　　

　　Repeated fluctuation of blood pressure may induce myocardial infarction.

　　

　　For the elderly with fragile blood vessels,

　　

　　be highly dangerous

　　

　　How to blow air conditioning healthily?

　　

　　Pay attention to these points!

　　

　　Air conditioning should be cleaned regularly.

　　

　　Whether it’s central air conditioning

　　

　　Or a stand-alone air conditioner at home

　　

　　It should be cleaned before use.

　　

　　It is recommended to clean it once every 1~2 months after use.

　　

　　Window ventilation is essential.

　　

　　Turn on the air conditioner

　　

　　Attention should be paid to frequent ventilation.

　　

　　It is recommended that every 2~3 hours.

　　

　　Just ventilate the room once.

　　

　　Ventilation for 10 to 15 minutes each time.

　　

　　Air conditioning wind blows upward.

　　

　　The temperature should not be too low.

　　

　　Cold air will stimulate sweat pores to contract suddenly.

　　

　　It is easy to cause dizziness, headache, runny nose,

　　

　　Symptoms such as joint pain.

　　

　　It is suggested that the temperature of air conditioner should be adjusted to 26≧

　　

　　The temperature difference between indoor and outdoor should not exceed 7≧

　　

　　When the air conditioner is turned on, the cold air sinks.

　　

　　So the wind had better blow upward.

　　

　　Avoid cold air blowing directly on your body.

　　

　　Drink more warm water.

　　

　　To prevent water loss from the body

　　

　　Causes dry skin and itchy throat.

　　

　　Drink plenty of warm water.

　　

　　Drink chrysanthemum tea, etc

　　

　　Eat more fresh fruits rich in vitamins.

　　Central air conditioning is an indispensable energy consumption operation system in modern buildings. Central air conditioning system not only provides people with comfortable living and working environment, but also consumes a lot of energy. According to statistics, the energy consumption of buildings in China accounts for about 30% of the total energy consumption. In buildings with central air conditioning, the energy consumption of central air conditioning accounts for about 70% of the total energy consumption, and it is increasing year by year. Therefore, how to efficiently use the energy and energy saving of central air conditioning system has become an urgent problem to be solved.So we can draw a preliminary conclusion, air conditioning for commercial It is helpful to the needs of the industry market and social development. https://puremind.com/product-category/puremind-air-conditioner/commercial-air-conditioner/

　　

　　The normal operation of the central air conditioning system, its energy consumption mainly has two aspects [1″ target=_blank>: on the one hand, it is the energy consumption of cold and heat sources to supply air handling equipment with cold and heat; On the other hand, in order to transport air and water, fans and pumps need energy to overcome the flow resistance. The energy consumption of central air conditioning system is affected by many factors, and many operation links have energy-saving measures. Therefore, energy-saving of central air conditioning is a comprehensive project. The following introduces several commonly used energy-saving measures in terms of energy consumption of cold and heat sources and power consumption.

　　

　　1. Energy-saving measures for cold and heat sources

　　

　　1.1 Temperature and humidity control

　　

　　From the air treatment process of central air conditioning system, it can be seen that the lower the indoor temperature and relative humidity in summer, the greater the energy consumption of system equipment; The higher the indoor temperature and relative humidity in winter, the greater the energy consumption of the system equipment, and the corresponding initial investment and operating costs also increase.

　　

　　Because everyone’s requirements for comfort are very different, there can be a wider comfort zone for civil central air conditioning. In this comfort zone, when cooling in summer, take a higher temperature and humidity value; When heating in winter, a certain energy-saving effect can be obtained by taking a lower temperature and humidity value. The change of temperature and humidity in the building is closely related to building energy saving. According to empirical statistics, if the set temperature is lowered by 1≧ in summer, the energy consumption will increase by 9%. If the set temperature is raised by 1≧ in winter, the energy consumption will increase by 12%. Therefore, it is an effective measure to control the temperature and humidity in the building within the precision range of the set value.

　　

　　In order to reduce energy consumption, the indoor temperature and humidity base of air-conditioned rooms should be raised as much as possible in summer and lowered as much as possible in winter under the condition of meeting production needs and human health. At present, some owners blindly pursue the realm of “cold enough” and greatly improve the design standard of indoor temperature and humidity, which not only wastes a lot of energy unnecessarily, but also produces the negative effect of comfort.

　　

　　The higher the temperature and humidity control precision of air conditioning system, the better the comfort and the more obvious the energy-saving effect. The accuracy of the signal measured by the front end of the air conditioning system directly affects the precise control degree of the central air conditioning system. Therefore, the measured signals, especially analog signals such as temperature and humidity, must be as accurate as possible.

　　

　　Also, BAS with high control accuracy must be selected to control the central air conditioner. Because BAS uses DDC (Direct Digital Controller) to directly control the opening of electric water valve without intermediate regulator; In addition, DDC contains a wealth of calculation and control software, such as PID algorithm, fuzzy control algorithm, genetic algorithm and so on, to ensure the control accuracy.

　　

　　1.2 cold source efficiency control

　　

　　The performance index to evaluate the refrigeration efficiency of cold source is COP (Coefficient Of Performance). Refrigeration coefficient refers to the amount of cold energy that can be obtained per unit power consumption. The refrigeration coefficient has nothing to do with the nature of refrigerant, but only depends on the temperature T0 of the cooled object and the coolant temperature Tk. The higher T0, the lower Tk and the higher the refrigeration coefficient. So don’t make the chilled water temperature too low and the cooling water temperature too high during the actual operation of the air conditioning system, otherwise the refrigeration coefficient will be low, which will consume a lot of work and high power consumption to produce unit cooling capacity, and increase the energy consumption of the building. The following measures can be taken to improve the efficiency of cold source:

　　

　　1) reduce the cooling water temperature

　　

　　The lower the cooling water temperature, the higher the refrigeration coefficient of the cooler. For every 1≧ increase in the supply temperature of cooling water, the COP of the chiller decreases by nearly 4%. To reduce the temperature of cooling water, it is necessary to strengthen the operation management of cooling tower. First of all, for the cooling tower that stops running, the valves in and out of the water pipes should be closed. Otherwise, because the water temperature from the stopped cooling tower is high, the temperature of the mixed cooling water will increase and the refrigeration coefficient of the cooler will decrease. Secondly, after the cooling tower is used for a period of time, it should be overhauled in time, otherwise the efficiency of the cooling tower will decrease and the cooling water cannot be fully cooled.

　　

　　2) increase the temperature of chilled water.

　　

　　The higher the temperature of chilled water, the higher the refrigeration efficiency of the chiller. When the temperature of chilled water supply is increased by 1≧, the refrigeration coefficient of the chiller can be increased by 3%, so don’t blindly reduce the temperature of chilled water in daily operation. First of all, don’t set the set temperature of chilled water of the cold machine too low. Secondly, the water valve of the stopped chiller must be closed to prevent some chilled water from taking the bypass pipeline, otherwise, the amount of water passing through the running chiller will be reduced, resulting in the temperature of chilled water being lowered to a too low level by the chiller.

　　

　　2. Energy-saving measures for power consumption

　　

　　2.1 Transportation energy consumption control

　　

　　Power consumption mainly refers to the electric energy consumed by fans and pumps in system operation. Calculation formula of input power from fan and water pump:

　　

　　(1) (W): input power; : volume flow; : indenter; Eta: efficiency

　　

　　From Formula (1), it can be seen that reducing power consumption can be considered from the following three aspects: reducing flow, reducing system resistance and improving the efficiency of fans and pumps. The following measures can be adopted in engineering practice:

　　

　　1) adopt large temperature difference.

　　

　　If the temperature difference between the supply and return water (or the return air) used to transport cold and hot water (or air) in the system is large, then when the ratio between it and the original temperature difference is m, it is known from the flow calculation formula that the flow rate is reduced to 1/m3 when the large temperature difference is used. At this time, the power required by the water pump or fan will be reduced to 1/m3. It can be seen that the energy-saving effect of increasing the temperature difference is obvious.

　　

　　On the premise of meeting the requirements of central air conditioning accuracy, personnel comfort and technology, the temperature difference of air supply should be increased as much as possible. It should be noted that the temperature difference between supply and return water should not be greater than 8≧.

　　

　　2) choose low flow rate.

　　

　　Because the power consumption required by pumps and fans is roughly proportional to the flow velocity in the pipeline system, in order to achieve energy-saving operation effect, high flow velocity should not be adopted in design and operation. In addition, the low flow rate in the main pipe is also beneficial to the stability of the hydraulic condition of the system. For example, changing the rotational speed of the fan can change the performance parameters of the fan. The power of the fan has a cubic relationship with the rotational speed, while the flow rate has a linear relationship with the rotational speed. Lowering the rotational speed can greatly reduce the energy consumption while reducing the flow rate. When the flow rate is reduced by 1/3, the energy consumption can be reduced by about 70.4%, and when the flow rate is reduced by 1/2, the energy consumption can be reduced by about 87.5%, and the efficiency of the fan is basically unchanged, and it can still work stably and efficiently.

　　

　　3) adopt energy-carrying medium with high conveying efficiency.

　　

　　Under normal circumstances, the energy consumption of transporting cold and heat energy with water is less than that with air, and the diameter of water pipes used to transport the same cold and heat energy is much smaller than that of air pipes, which occupies a much smaller building space. This is also one of the main reasons for the rapid development of central air conditioning in recent years.

　　

　　Therefore, for the centralized refrigeration mode, in principle, the chilled water prepared by the equipment in the computer room should be transported as far as possible to the vicinity or use point of each central air-conditioning partition, and the air should be treated by the terminal non-independent central air-conditioning units (such as cabinet air-conditioning units and fan coils) for local use or for use in nearby rooms.

　　

　　2.2 VAV system control

　　

　　VAV system is an energy-saving countermeasure against the shortcomings of power consumption in air supply system. VAV system can be divided into two types: one is AHU！VAV system of air conditioner; One is the indoor fan variable air volume system (FCU-VAV system) in FCU system. AHU-VAV system is to fix the air supply temperature in the whole air duct system and adjust the air supply volume of the blower to cope with the change of indoor air conditioning load. In FCU-VAV system, the cold water supply is fixed, and the indoor FCU is equipped with a stepless power controller to change the air supply, that is, to change the heat exchange rate of FCU to adjust the indoor load change. These two methods can reduce the power consumption of the blower by adjusting the air volume, and at the same time, they can also increase the operating efficiency of the heat source machine and save the power consumption of the heat source, so they can achieve energy-saving effects in both air supply and heat source.

　　

　　The cooling capacity sent into the room can be determined by the following formula:

　　

　　2

　　

　　Where: c is the specific heat capacity of air, kj/(kg≧); ρ is the air density, Kg/m3; L is the air supply volume, m3/S; Tn is the indoor temperature,≧; Ts is the supply air temperature,≧; Q is the heat absorbed (or put) into the room, KW.

　　

　　If the air supply temperature is set as a constant and the air supply volume L is changed, different Q values can be obtained to keep the room temperature unchanged. Variable air volume control can adopt an air supply device that automatically adjusts the air supply volume according to the change of indoor load. When the indoor load decreases, it can keep the air supply parameters unchanged (no need to reheat) and keep the indoor temperature stable by automatically reducing the air volume. In this way, it can not only save the reheat required by the constant air volume system to increase the air supply temperature, but also reduce the power consumption of the fan and the cooling capacity of the refrigerator due to the reduction of the treated air volume. According to various data, VAV can save energy by 30% ~ 50% compared with constant air volume.

　　

　　2.3 Frequency conversion control

　　

　　In most buildings, the central air conditioning is at the maximum load only for a few days in a year. The cooling load of central air conditioning is always changing dynamically, such as the changes of various factors such as morning and evening, climate, passenger flow and activity content, which affect the cooling load of central air conditioning in real time. Generally, the cooling load fluctuates in the range of 5 ~ 60%, and most buildings are at least 70% in this situation every year. However, most central air conditioners are driven by maximum cooling load and maximum power due to system design. In this way, the contradiction between the actual cooling load and the maximum power output is caused, resulting in a huge waste of energy. This contradiction can be solved by adopting frequency conversion control.

　　

　　1) Fan and water pump frequency conversion control

　　

　　In the past, the AC motor itself didn’t adjust the speed, so the central air conditioning system had to rely on baffles and valves to adjust the air and water flow, and a lot of electric energy was wasted on baffles and valves. If the fan water pump is regulated by frequency conversion, the energy wasted on baffles and valves will be saved, and the average energy saving effect of each pump will be considerable.

　　

　　For the fan water pump, according to the principle of fluid mechanics, the parameters under similar working conditions have the following relationship [2″ target=_blank>:

　　

　　3

　　

　　Where Q1, H1, n1 and N1 are the flow, lift, power and rotation speed before the rotation speed change, respectively;

　　

　　Q2, H2, n2, N2: the flow, lift, power, and rotation speed after the rotation speed is changed respectively.

　　

　　According to Formula (3), the flow rate is proportional to the rotational speed, the pressure is proportional to the square of the rotational speed, and the power consumed is proportional to the cubic power of the rotational speed. For variable frequency speed regulation, the speed n is basically proportional to the power frequency f, when the power frequency f decreases, the motor speed also decreases, and the required power decreases rapidly with the cubic power of the speed, which shows that the energy-saving effect is very remarkable. Take the fan as an example, if the required air volume is 80% of the rated air volume, the speed will also drop to 80% of the rated speed, and the shaft power will drop by 51.2%; When the required air volume is 50% of the rated air volume, the shaft power drops by 12.5%. This power saving effect is also very impressive. It has been proved that the frequency conversion control of fans and pumps can save energy by 40% ~ 50%.

　　

　　2) Frequency conversion control of water chillers

　　

　　Because the compressor does not rule out the possibility of long-term operation under full load, the capacity of the motor can only be determined according to the maximum demand, so the design margin is generally large. In actual operation, the proportion of light load operation time is very high. Frequency conversion control is adopted to adjust the speed of compressor, so as to control the refrigeration capacity and keep the refrigeration unit in the best (most reasonable) operation state. Frequency conversion control improves the efficiency of air conditioner and the operation effect of refrigeration unit, thus realizing energy saving.

　　

　　The principle of variable frequency compressor is to adjust the displacement of compressor per unit time by adjusting the speed of compressor, so as to achieve the purpose of adjusting the refrigeration capacity. The mathematical relationship between refrigeration capacity and compressor frequency is as follows:

　　

　　4

　　

　　Where n is the rotational speed, f is the frequency of the motor, p is the polar logarithm of the motor, s is the slip of the motor, λ is the leakage coefficient, Ps is the suction pressure, vh is the suction volume, ni is the polytropic index, εi is the pressure ratio (exhaust/suction), δ0 is the relative pressure loss coefficient, and Zs and Zd are the actual gas compressibility coefficients, which are the average energy efficiency ratio.

　　

　　According to Formula (4), the refrigeration capacity is directly proportional to the frequency, so the refrigeration capacity can be controlled by frequency conversion regulation, thus achieving the energy-saving effect.

　　

　　Some adjustment methods (such as adjusting the valve opening and changing the blade angle) can not reduce the operating efficiency of the motor even if the demand is small. After adopting frequency conversion speed regulation, when the demand is small, the speed of motor can be reduced and the running power of motor can be reduced, thus further realizing energy saving. It has been proved that the frequency conversion control of water chillers can save energy by 20% ~ 30%.

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Athens, May 13 (Reporter Chen Gang) Greek Prime Minister Mitsotakis criticized on the 13th that the new President of North Macedonia Davkova’s use of Macedonia when mentioning the name of the country in his inaugural speech was inconsistent with the previous agreement reached between the two countries.

North Macedonia President-elect Davkova was sworn in on the 12th. In her inaugural speech, she used Macedonia when referring to her country’s name, causing Greek Foreign Minister Jera Petritis to leave the table on the spot.

Mizotakis said North Macedonia’s new president’s call of his name was unacceptable, violating the agreement between the two countries.

The Office of the President of North Macedonia later issued a statement saying that Davkova insisted that she had the right to use the name of Macedonia and believed that her practice was in line with European values and principles.

European Commission President Von der Leyen and European Council President Michel successively issued articles on social media pointing out Davkova’s actions were inappropriate. Von der Leyen said on social media: If North Macedonia wants to successfully join the EU, the most important thing is to continue on the path of reform and fully respect binding agreements.

Macedonia became independent from Yugoslavia in 1991 and established its constitutional name as the Republic of Macedonia. Greece believes that this name implies that it has territorial and cultural heritage requirements for the Greek province of Macedonia. Due to a name dispute, Greece, a member of the European Union and NATO, opposes the Republic of Macedonia’s accession to the European Union and NATO.

After years of mediation negotiations, the two countries reached an agreement in June 2018 to change Macedonia’s name to the Republic of North Macedonia as a condition for Greece to agree to its accession to the European Union and NATO. In January 2019, the two parliaments successively approved the agreement. In February 2019, Macedonia officially changed its name to the Republic of North Macedonia.

　　There are many kinds of refrigeration methods, such as gas expansion refrigeration, liquid gasification refrigeration, vortex tube refrigeration and thermoelectric refrigeration. Among them, liquid gasification refrigeration is the most widely used, and its working principle is to realize refrigeration by using the heat absorption of liquid gasification.After that, Puremind RV Air Conditioners Not afraid of the future, dare to fight and fight, and won applause again and again in the market. https://puremind.com/

　　

　　1, the working principle of air conditioning (mainly refrigeration, heating on the contrary):

　　

　　The high-temperature and high-pressure refrigerant discharged from the compressor flows through the outdoor heat exchanger through the four-way valve, and dissipates heat to the outdoor air through heating transfer, and the refrigerant changes from gaseous state to liquid state-throttles and depressurizes through capillary (or solenoid valve)-one-way valve-filter-two-way valve (outdoor high-pressure pipe)-enters the indoor heat exchanger to absorb heat (realize refrigeration)-outdoor three-way valve (outdoor low-pressure pipe). Complete a single-loop refrigeration cycle.

　　

　　2. Types of components in refrigeration system:

　　

　　The air conditioning refrigeration system is mainly composed of four parts and some auxiliary equipment in the refrigeration system.

　　

　　The four major pieces are:

　　

　　compressor

　　

　　condenser

　　

　　Throttle mechanism

　　

　　Evaporator composition.

　　

　　Auxiliary equipment:

　　

　　Oil separator;

　　

　　Drying filter;

　　

　　Liquid storage tank;

　　

　　Electromagnetic four-way reversing valve;

　　

　　Solenoid valve; Check valve

　　

　　3, the working principle of each component

　　

　　Compressor: As the “heart” of refrigeration system, it has an important influence on the performance, noise, energy consumption, vibration and service life of air conditioning. According to the principle of thermodynamics, it can be divided into volumetric type and velocity type.

　　

　　Volumetric type: a certain volume of gas is sucked into the cylinder and the internal volume of the cylinder is changed to realize gas compression and forced discharge.

　　

　　Speed type: make the inhaled gas get a certain speed, and then slow down, so that kinetic energy can be converted into pressure energy and then discharged. The growth of gas is converted from speed.

　　

　　one

　　

　　Scroll compressor: It is formed by meshing two vortexes of stator and rotor.

　　

　　Rotor compressor: it consists of spindle with eccentric wheel, cylinder, sleeve, air inlet, slide plate, spring, exhaust valve and exhaust port.

　　

　　Condenser: The condenser transfers the refrigerating capacity of the evaporator in the refrigeration system to the environmental medium (cooling water or air) together with the power consumption of the compressor. According to cooling, it can be divided into air-cooled type, water-cooled type and evaporative type. When cooling, it mainly radiates heat to the outside, and when heating, it absorbs heat to the outside.

　　

　　Evaporator: The main function of the evaporator is to boil and evaporate the low-temperature and low-pressure refrigerant liquid that has entered the throttle in the evaporator, absorb the heat of the cooled medium, and then become low-pressure saturated (usually overheated) vapor itself, which is continuously sucked away by the compressor. In other words, the evaporator is a heat exchange device that absorbs heat (that is, outputs cold energy).

　　

　　Throttle element: Throttle element is one of the four main elements in the refrigeration system. Its main function is to throttle and reduce the pressure of high-pressure liquid refrigerant, ensure the pressure difference between condenser and evaporator, and make the refrigerant entering the evaporator absorb heat and evaporate at the required low pressure, thus achieving the purpose of refrigeration and cooling. Adjust the refrigerant flow into the evaporator to adapt to the load change of the evaporator and make the system run normally.

　　

　　Capillary: It is a very thin tube, usually with an inner diameter of 0.5 ~ 2.5 mm and a length of 1 ~ 5 m.. When the refrigerant flows in the tube, it is necessary to overcome the resistance in the tube, which naturally produces a certain pressure drop.

　　

　　Capillary characteristics: Because it is in the normally open state, when the compressor stops, the high and low pressure can be quickly balanced, which is conducive to the compressor starting again. Simple structure, convenient manufacture and low price. For the heat pump system, there is no import and export problem in the throttling process of refrigerant in capillary [this article source: refrigeration encyclopedia WeChat official account” target=_blank>. Using capillary refrigeration system, the performance of the unit is very sensitive to the refrigerant charge. When the operating conditions of the refrigeration system change, the capillary tube has poor ability to adjust the refrigerant flow. Due to the small inner diameter of capillary and long pipeline, it is easy to be blocked, so attention should be paid to the drying and cleaning of the system. Generally, a dry filter is set in front of the capillary to prevent clogging.

　　

　　Thermal expansion valve: the regulating valve that controls the liquid supply of evaporator, and it is also the throttle valve of refrigeration device. Thermal expansion valve uses the change of superheat of refrigerant at evaporator outlet to adjust the flow. According to different structures, it can be divided into internal balance type and external balance type.

　　

　　Disadvantages of thermal expansion valve: low control precision and limited adjustment range. The diaphragm deformation of valve body is limited, which makes the change range of valve needle opening smaller, so the adjustment range of flow is small. When large flow regulation is required, it cannot be met. The high-temperature gas at the place where the signal feedback has a lag evaporator must first heat the shell of the temperature sensor, which has a large thermal inertia, leading to the lag of the reaction.

　　

　　2

　　

　　Electronic expansion valve: the application of electronic expansion valve overcomes the shortcomings of thermal expansion valve and provides conditions for the intelligence of refrigeration device. The electric signal generated by adjusting parameters is mainly used to control the voltage or current applied to the expansion valve, so as to achieve the purpose of adjustment, so that the control system of the electronic expansion valve is complicated and the price is high.

　　

　　Electronic expansion valve classification:

　　

　　Electromagnetic electronic expansion valve;

　　

　　Electric electronic expansion valve.

　　

　　4. Auxiliary equipment of refrigeration system

　　

　　Oil separator: The high-pressure gas (gaseous working medium and lubricating oil) from the compressor enters the oil separator to separate the lubricating oil from the working medium gas and flows down along the inner wall of the cylinder. The working gas is led out of the oil separator from the central pipe through the porous baffle. The separated lubricating oil is concentrated in the lower part of the oil separator and can be discharged regularly, or the lubricating oil can be automatically returned to the crankcase of the compressor by using the ball valve.

　　

　　Drying filter: The function of drying filter is to absorb moisture in refrigeration system, prevent impurities in the system from passing through, and prevent the pipeline of refrigeration system from being blocked by ice and dirt. Because the most easily blocked part of the system is the capillary (or expansion valve), the drying filter is usually installed between the condenser and the capillary (or expansion valve).

　　

　　Liquid storage tank: During the operation of the refrigeration system, the circulating amount of refrigerant in the system will change due to the change of working conditions or the adjustment of refrigeration capacity. Setting the liquid storage tank can balance and stabilize the refrigerant circulation in the system by using the liquid storage capacity of the liquid storage tank, so that the refrigeration system can be in normal operation. In addition, when a component in the refrigeration system fails and needs to be dismantled and repaired, the system refrigerant can be recovered to the liquid storage tank through certain operation methods.

　　

　　The liquid storage tank is generally arranged between the condenser and the throttling element, so that the refrigerant liquid in the condenser can smoothly enter the liquid storage tank. The position of the liquid storage tank should be lower than that of the condenser.

　　

　　Electromagnetic four-way reversing valve: after the electromagnetic coil is energized, it changes the action direction of the valve block in the valve body and changes the flow direction of the refrigerant. So as to achieve the purpose of cooling or heating.

　　

　　three

　　

　　Solenoid valve: Solenoid valve is usually installed in front of the expansion valve to directly control the amount of refrigerant entering the evaporator. It can also be installed before the compressor unloading cylinder to control the unloading of the compressor cylinder.

　　

　　There are two kinds:

　　

　　Direct opening and closing solenoid valve;

　　

　　Indirect solenoid valve.

　　

　　One-way valve: The one-way valve is usually connected in parallel with the auxiliary capillary, and the two are connected in series with the main capillary. One-way valve is a tubular element with a movable spherical or hemispherical plug made of stainless steel or nylon. Combined with capillary tube, it can adapt to two different operating conditions of refrigeration and heating.

　　

　　5. Types and States of Refrigerant

　　

　　Air conditioning refrigerants mainly include R22, R410A and R32.

　　

　　R22 is a medium-temperature refrigerant, with the standard of -40.8 degrees, the solubility of water in R22 is very small, and it is mutually soluble with mineral oil, and R22 does not burn or explode, with little toxicity and strong permeability.

　　

　　R410A is a HFC refrigerant which is composed of R32 and R125 by 50% and 50% by mass. [This article comes from WeChat official account, a refrigeration encyclopedia” target=_blank>, which belongs to a near azeotrope, and its thermodynamic properties are very close to that of a single refrigerant. Compared with R22, R410A’s condensation pressure is increased by 1.6 times, and it is a high-pressure refrigerant, so it is necessary to improve the compression strength of the system.

　　

　　R32 is the abbreviation of difluoromethane, which is a kind of coolant with zero ozone loss potential. It is a gas at room temperature and a colorless and transparent liquid under its own pressure. It is soluble in oil and insoluble in water, and it is an energy-saving and carbon-reducing environment-friendly non-toxic refrigerant, but it is flammable and explosive!

　　

　　6. Refrigerant status

　　

　　Saturated refrigerant: Vapor-liquid conversion in saturated refrigerant is in transport equilibrium, and liquid and gas at this time are in saturation.

　　

　　There is a one-to-one correspondence between saturation temperature and saturation pressure, and the saturation pressure increases with the increase of saturation temperature, and one of them will change and the other will change accordingly. In the system, the refrigerant in the evaporator absorbs heat and the refrigerant in the condenser releases heat, where the refrigerant is saturated.

　　

　　Superheat: Under a certain pressure, the temperature of superheated steam exceeds the saturation temperature.

　　

　　Overheating: the temperature of refrigerant vapor in superheated refrigerant is higher than the saturation temperature under the corresponding saturation pressure, and the liquid refrigerant will overheat after evaporation. In the case of overheating, there is no one-to-one correspondence between the temperature and pressure of refrigerant gas.

　　

　　Near the outlet of the evaporator, the refrigerant continues to absorb heat after complete evaporation and becomes superheated refrigerant with a temperature higher than the saturation temperature. The refrigerant enters the compressor through the suction pipe in case of overheating.

　　

　　Supercooling: The liquid temperature of the supercooled refrigerant is lower than the saturation temperature at the corresponding saturation pressure, and supercooling will only occur when there is no steam in the fluid refrigerant. In the case of supercooling, there is no one-to-one correspondence between the temperature and pressure of refrigerant liquid.

　　

　　Between the outlet of the condenser and the throttle valve, the refrigerant may continue to cool exothermically and become supercooled after condensing into saturated liquid.

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According to a report by the Russian News Agency on March 20, Russian Foreign Ministry Spokesperson Zakharova said at a press conference that NATO has chosen a new direction of confrontation with Russia.

Reported that Zakharova said: NATO’s top priority is to open up a second front against my country in the Transcaucasia and reignite the war throughout the region.

She said NATO was not satisfied with Russia’s conciliatory policies in the Transcaucasia region.

The report mentioned that NATO Secretary General Stoltenberg visited Yerevan, the capital of Armenia, on the 19th and called on Armenia and Azerbaijan to sign an agreement aimed at paving the way for the normalization of relations between the two countries.

Russian Presidential Press Secretary Peskov said that NATO’s attempts to expand its influence may not strengthen stability in the Caucasus region. (Compiled by Zheng Yu)

Related news recommendations:

NATO troops exercise near Russian border

According to a report by the Russian News Agency on March 20, the Polish Ministry of Defense released a message saying that the NATO Northeast Division, composed of multinational forces, practiced defensive operations during exercises held in imaginary areas near the Russian border.

Poland’s Ministry of Defense said: During the Loyalty Lecda 2024 exercise, soldiers of the multinational Northeast Division were given such a task to carry out defensive operations in an imaginary area similar to the situation in northeastern Poland.

Reported that the command department of NATO’s Northeast Division refused to disclose details of the exercise content.

According to reports, the NATO Northeast Division headquarters is located in Elblong, Poland, and its mission is to coordinate the actions of NATO troops deployed in Poland, Lithuania, Latvia and Estonia. (Compiled by Liu Yang)

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Recently, a cat in Belgorod Oblast, Russia, became popular on the Internet for its heroic savior. This cat named Archie has won widespread praise from people for its extraordinary bravery and loyalty.

It is understood that an explosion occurred near the building where the hostess’s family lived, and the situation was very critical. At this time, Archie cat stepped forward and used its tail to block the shrapnel that broke through the window and flew towards the hostess’s head. Although this move injured Archie himself, it successfully protected the safety of the hostess.

Subsequently, the veterinarian provided emergency treatment to Archie and removed a metal fragment from its hind leg. Fortunately, despite the injury, Archie’s vital organs were not damaged. Currently, it is recovering and believes that it will soon regain its former vitality.

Archie’s heroic behavior not only made people lament his loyalty and bravery, but also made people cherish and respect life more.

　　Improper use of air conditioningAs it happens, many people are killed Puremind Commercial Air Conditioners And bring more benefits, make it flourish, and promote the industry greatly. https://puremind.com/puremind-hot-sale/

　　

　　Not only will it increase electricity consumption,

　　

　　It may even affect your health.

　　

　　Today, follow the Shanghai Health Promotion Center.

　　

　　Let’s learn the “cold knowledge” of air conditioning use ~

　　

　　Don’t “open and close for a while”

　　

　　I wonder if you have had such an experience?

　　

　　Caught in the strange circle of air conditioning turning on cold and turning off hot, repeated operation is always “cutting suitable”; Or go out and get a courier, thinking that it is more energy-saving to turn off the air conditioner first.

　　

　　In fact, often this behavior of frequently starting the air conditioner increases the power consumption and is not conducive to the maintenance of the air conditioner.

　　

　　Studies have proved that air conditioning “turns on and off for a while” does not actually save electricity. Therefore, if you only go out for a short time, you don’t have to turn off the air conditioner and turn it on again.

　　

　　Pay attention to “humidity” and “temperature”

　　

　　The muggy air has a high humidity, so it is uncomfortable to adjust the temperature. At this time, try to turn on the “dehumidification mode” after air conditioning refrigeration, and the air will become more refreshing and comfortable.

　　

　　If you need to stay in an air-conditioned room for a long time, remember to drink water properly to avoid the loss of water.

　　

　　Practice has proved that it is most appropriate to control the indoor and outdoor temperature difference at 6-8≧, mainly to reduce the burden on the thermoregulation center and avoid the symptoms of dizziness, headache and dry skin and mucosa. Therefore, the air conditioning temperature is set at 26 to 28≧.

　　

　　Don’t sweat and rush into the air-conditioned room.

　　

　　In hot summer, it is easy to sweat when you move a little and bask in the sun. Do you just want to rush into the air-conditioned room? At this time, you should be careful that the disease will come to you.

　　

　　For the general population, sudden cold and heat are easy to catch a cold, have a fever and have diarrhea; It is even more dangerous for patients with hypertension and coronary heart disease.

　　

　　The cardiovascular system in the original thermal environment is in a state of relaxation, and the sudden cooling air after entering the air-conditioned room makes the blood vessels contract urgently, which is prone to dangerous situations such as myocardial infarction.

　　

　　Therefore, don’t rush into the air-conditioned room after sweating, let the sweat collect first, or wipe your body with a dry towel first. When the air conditioner is just turned on, it should not be adjusted to a too low temperature, and at the same time, it should avoid cold air blowing directly on the head, neck and waist and abdomen.

　　

　　Do a good job cleaning

　　

　　The cleaning problem of air conditioning is often easily overlooked, and the bacteria hidden in it will take advantage of the opportunity to cause “air conditioning disease.”

　　

　　Legionella, which lurks in the daily artificial water environment, is such a pathogen. Water contaminated by bacteria can be inhaled by human body in the form of aerosol. After people are infected with Legionella, there will be symptoms similar to pneumonia, such as high fever, chills, fatigue, muscle pain, etc., which may even be life-threatening.

　　

　　The air conditioning system is the main “hiding point” of Legionella, so it is necessary to clean and disinfect the air conditioning; If it is a central air conditioner, the deposited cooling tower water should be replaced and the attached “dirty things” should be removed in time. Don’t forget to clean the casing and filter screen after the “air conditioning season”.

　　

　　In addition, it is recommended to open the window for ventilation every 2-3 hours to ensure the cleanliness of indoor air.

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Rio de Janeiro, March 12 (Reporter Zhao Yan) The Brazilian Federal Senate announced at a plenary session on the 12th the establishment of a parliamentary investigation committee to investigate cases of fixing football match results, hoping to severely punish match-fixing.

This committee consists of 11 members, appointed by representatives from all parties in Parliament. According to a report by Brazil’s “Sao Paulo” on March 4, of the approximately 9000 Brazilian football matches monitored by sports betting radar in 2023, 109 (approximately 121% of the total) were suspected of playing match-fixing, ranking first in the world.

On the 11th of this month, the Prosecutor’s Office of the Federal District of Brasilia issued a search and arrest warrant against two Santa Maria players, accusing them of directly participating in match-fixing in two games in the state league. Evidence collected by the investigation showed that the two men used methods including deliberately being awarded penalty kicks, deliberately marking errors, and even making an own goal to make the team lose the game.

In December last year, the Brazilian Congress passed the online sports betting bill, which officially came into effect after being approved by President Lula. At the end of January this year, the federal government established a Bonuses and Gaming Secretariat, which is responsible for regulating and supervising the sports betting and online gambling industries.

　　It’s getting hot, and it’s time to turn on the air conditioner. But can you really use air conditioning? Is it only cooling in summer and heating in winter? Air-conditioning remote controllers are generally equipped with a variety of use modes, and different modes have different use effects. Let’s take a look at it.Before that, commercial heating and cooling The market has also soared for a time, which has attracted the attention of a wide range of investors. https://puremind.com/product-category/puremind-air-conditioner/commercial-air-conditioner/

　　

　　Cool feeling mode

　　

　　Applicable people: afraid of heat and cold.

　　

　　Blowing the air conditioner in summer is cool, because the room temperature is lowered, and because the cold air blown by the air conditioner blows on the body, it plays the role of an electric fan.

　　

　　The principle of the “cool feeling” function is simple: control the angle and speed of the air outlet to prevent the air conditioner from blowing at people-the traditional way is to adjust the angle of the air deflector and the speed of the fan, and the new air conditioner is even equipped with an infrared probe to prevent the wind from blowing directly at people, which is very friendly to people who are afraid of cold stars.

　　

　　Air supply mode

　　

　　Applicable scenario: when it is not too hot

　　

　　Air conditioning is a combination of “cooling/heating+fan”, and the “air supply” function is to turn on the fan instead of starting the compressor, electric heating wire and other temperature-related components of the air conditioning.

　　

　　If you want to improve the air quality, breathe and smell, you need air conditioning with fresh air system.

　　

　　Eco mode

　　

　　Applicable scene: before going to sleep

　　

　　”eco”, the abbreviation of economic, is also called “energy saving” mode.

　　

　　It is suggested that the air conditioner can be changed to this mode before going to bed. When you fall asleep at a comfortable room temperature, the air conditioner will change the temperature, increasing it in summer and decreasing it in winter. In short, it will reduce the power consumption until it is completely turned off, that is, the “sleep” mode.

　　

　　Dehumidification mode

　　

　　Applicable scene: hot and humid weather

　　

　　Both “dehumidification” and “refrigeration” modes will produce refrigeration effect. The difference is that after the “dehumidification” mode is turned on, the air conditioner will appropriately cool the indoor air, let the water vapor condense into water, and then discharge it to the outside-reducing the indoor humidity, and people’s body temperature will be cooler. The main purpose of the “refrigeration” mode is to reduce the indoor temperature, and the water vapor in the condensed air is an incidental effect.

　　

　　From the effect point of view, after opening the “dehumidification” mode, although the air conditioning temperature is not very low and it does not consume too much electricity, it will be more comfortable.

　　

　　It should be noted that this function is only effective in areas with humid climate. If you live in a dry area, this function is not recommended.

　　

　　Automatic mode

　　

　　Applicable people: people who need indoor constant temperature and people who use company air conditioning.

　　

　　To choose this mode, you need to set a temperature first, say 26 degrees Celsius. If the room temperature is lower than 26 degrees Celsius, the air conditioner will start heating; If the room temperature is higher than 26 degrees Celsius, the air conditioner will start to cool.

　　

　　Auxiliary heating mode

　　

　　Applicable scene: when you just enter the house in winter and are about to be frozen.

　　

　　There are two ways to heat by air conditioning. One is a porter who relies on heat-compressor. From the thermodynamic point of view, using compression mechanism to save heat and electricity, but the heating speed is slow, and when it is particularly cold outdoors, such as below 0 degrees Celsius, the heating efficiency will become low.

　　

　　The other is the producer of heat-electric heating wire. “Auxiliary heating” is the option of turning on the electric heating wire, which can assist the compressor to achieve the effect of rapid heating. After the room temperature reaches the set temperature, just keep the temperature by the compression mechanism. At this time, the “auxiliary heating” function can be turned off in order to save electricity.

　　

　　Everyone can use these functions as much as possible. After all, we spent thousands of dollars to buy an air conditioner, and if we don’t drain all its functions, we will lose money!