What Is a Refrigerant Chart?

Refrigerant, also called refrigerant, is the working medium of the refrigeration cycle. It uses the phase change of the refrigerant to transfer heat. The refrigerant absorbs heat when it vaporizes in the evaporator and exotherms when it condenses in the condenser. There are currently more than 80 substances that can be used as refrigerants. The most commonly used are ammonia, freons, water, and a few hydrocarbons. In September 1987, a specialized international conference was held in Montreal, Canada, and the Montreal Protocol on Ozone Depletion was signed. It entered into force on January 1, 1989, and was effective for Freon's R11, R12, and R113. , R114, R115, R502, and R22 are restricted. The second meeting of the parties to the Protocol was convened in London in June 1990, adding restrictions on the production of all CFCs, carbon tetrachloride (CCL4) and methyl chloroform (C2H3CL3). The complete cessation of production of the above substances may be postponed to 2010 in developing countries. In addition, a control schedule for the transitional substance HCFC after 2020 is proposed. R123 and R134a in HCFC are replacements for R12 and R22.

Refrigerant, also called refrigerant, is the working medium of the refrigeration cycle. It uses the phase change of the refrigerant to transfer heat. The refrigerant absorbs heat when it vaporizes in the evaporator and exotherms when it condenses in the condenser. There are currently more than 80 substances that can be used as refrigerants. The most commonly used are ammonia, freons, water, and a few hydrocarbons. In September 1987, a specialized international conference was held in Montreal, Canada, and the Montreal Protocol on Ozone Depletion was signed. It entered into force on January 1, 1989, and was effective for Freon's R11, R12, and R113. , R114, R115, R502, and R22 are restricted. The second meeting of the parties to the Protocol was convened in London in June 1990, adding restrictions on the production of all CFCs, carbon tetrachloride (CCL4) and methyl chloroform (C2H3CL3). The complete cessation of production of the above substances may be postponed to 2010 in developing countries. In addition, a control schedule for the transitional substance HCFC after 2020 is proposed. R123 and R134a in HCFC are replacements for R12 and R22.

Chinese name

Air conditioning refrigerant

nickname

Refrigerant

Attributes

Working medium of refrigeration cycle

Features

Transfer of heat using refrigerant phase change

Main characteristics of air conditioning refrigerant

(1) Does not damage the ozone layer. Its molecular formula contains chlorine, so its ozone depletion potential (ODP) is 0.055. The global warming potential (GWP) is 0.35.

(2) Very low toxicity. The permissible concentration is the same as R22, which is 1000 ppm.

(3) Non-combustible. The flammable polarity in air is zero.

(4) High chemical and thermal stability

(5) Water solubility is almost the same as R22.

(6) is a mixed refrigerant consisting of two refrigerants

(7) Not compatible with mineral oil or alkylbenzene oil. (Compatible with POE [Ester Lubricants], PVE [Ether Lubricants])

Air-conditioning refrigerant operation principle

When the air conditioner is used for cooling operation, the low-temperature and low-pressure refrigerant gas is sucked into the compressor and pressurized into high-temperature and high-pressure refrigerant gas.

Refrigerant Jar

, The high-temperature and high-pressure refrigerant gas passes through the condenser (generally air-conditioning is air-cooled, that is, the outdoor unit's heat-dissipating copper pipe) to release heat in the outdoor heat exchanger, and becomes a medium-temperature and high-pressure liquid (the heat is taken away by the outdoor circulating air). The medium-temperature and high-pressure liquid becomes low-temperature and low-pressure liquid after being expanded and decompressed by the capillary tube. The low-temperature and low-pressure liquid refrigerant passes through the evaporator (copper tube of the indoor unit) and absorbs heat and evaporates to become low-temperature and low-pressure gas (indoor air passes through the heat exchanger The surface is cooled down to achieve the purpose of reducing the indoor temperature), and the low-temperature and low-pressure refrigerant gas is sucked into the compressor and circulated in this way.

In general, air-conditioning refrigerant is a cycle of compression-condensation-expansion-evaporation in the air-conditioning system.

Air conditioning refrigerant fluorination method

Under normal temperature and pressure, R410A is a non-azeotropic mixed refrigerant of fluoroalkane without chlorine. It is a colorless gas and stored in steel cylinders.

Based on the characteristics of R410a, the application practice of using R410a instead of HCFC22 for a certain room air-conditioning system was analyzed theoretically and the system was matched. The experimental results show that under the same conditions, compared with HCFC22, the heat transfer coefficient is increased, and the flow resistance is reduced. After the system optimization and matching design, the performance (COP) is greatly improved, reaching the European market level A energy efficiency level.

Generally we may use low pressure and static raises.

1. The air conditioner starts to cool and then starts crying from a low pressure. When it is 0.35 ~ 0.55Mpa, it is OK. Then observe the cooling effect of the air conditioner. If possible, the measured high pressure cannot exceed 2.2Mpa.

2. When the air conditioner is disabled, add fluorine from the place where the fluorine is added. It is suitable when the system pressure reaches 0.8 ~ 0.9Mpa.

3 Let the air conditioner run for 30 minutes and check carefully.

4. For the correct method of filling, be sure to take your time slowly. After adding a bit, let the air conditioner run for about 10 minutes, then measure the pressure and current, and inevitably add it at different times. You cannot use the current pressure and current as standards. In that case, it may have been increased. When adding fluoride in winter, the four-way valve coil can be disconnected, and the indoor temperature sensing head can also be artificially made to reach a cooling temperature to start cooling. Sometimes the air conditioner can also be operated in dehumidification mode, and its temperature requirements are not very high.

Air conditioning refrigerant test process

(1) Pressure measurement

The measured low pressure is 0.35 ~ 0.55Mpa. If it's too high, it's more, if it's too low, it's less. The high pressure cannot exceed 2.2Mpa.

(2) Listen to the sound

If the sound is too loud and dull, it may be caused by adding more fluorine. If the sound is too low, it means that the volume is not enough.

(3) Measuring temperature

The suction pipe is cold and has dew condensation; the exhaust pipe temperature is about 80 degrees; the condenser temperature is about 55 degrees; the compressor suction pipe is cold and there is dew, and the exhaust pipe is very hot; the temperature of the evaporator is lower than the environment The temperature is about 15 degrees.

(4) Measuring working current

The total current is close to the rated current. If the current is too large, it is added more. If the current is too small, it is added too little. This requires the system and circuit to be tested under normal conditions, because the working current of the compressor has a large relationship with the suction pressure of the compressor. The higher the suction pressure, the higher the current, and the lower the suction pressure, the lower the current. If it is blocked, the working current of the compressor will be very low and the sound of the compressor will be abnormal.