R290 flammable R32 will explode? Talk about air conditioning refrigerants

 Refrigerant, also known as refrigerant and refrigerant, also has another well-known name, called snow seed. We often say that adding snow and Freon is to add new refrigerant to the air conditioner.
The refrigerant we are most familiar with is Freon. In our impression, freon is an environmentally friendly substance. If Freon leaks into the atmosphere, it will destroy the ozone layer of the atmosphere and form an ozone hole.
In fact, freon is not just a substance. Freon can be roughly divided into three categories, including chlorofluorohydrocarbons, hydrochlorofluorocarbons and hydrofluorocarbons. What will break the ozone layer is actually chlorofluorohydrocarbons in freon, and it is not fluorine that destroys ozone, but chlorine.
Although hydrochlorofluorocarbons also contain chlorine, their damage to the ozone layer is much lower than that of hydrochlorofluorocarbons. Hydrofluorocarbons have almost zero damage to the ozone layer because they do not contain chlorine. In addition, freon is also a greenhouse gas. Although the concentration of freon in the atmosphere is significantly lower than that of other greenhouse gases, its greenhouse effect is 3400 ~ 15000 times that of carbon dioxide.
Therefore, refrigerants usually introduce ozone layer destruction potential value (ODP) and global warming coefficient value (GWP) to measure their impact on the environment. The lower the ODP and GWP values are, the more environmentally friendly they are.
1. R22 refrigerant
R22 refrigerant belongs to hydrochlorofluorocarbons, and its chemical name is difluoro monochloromethane. R22 refrigerant is one of the most used refrigerants in the past. Most of our old air conditioners may use R22 refrigerant.
However, the ozone layer destruction potential (ODP) of R22 refrigerant is 0.05 and the global warming coefficient (GWP) is 1700, which will not only destroy the ozone layer, but also aggravate the greenhouse effect. For environmental reasons, R22 refrigerant is being phased out. According to the Montreal agreement, China is also phasing out products using R22 refrigerant, which only exists in some fixed frequency air conditioners.
2. R410A refrigerant
R410A refrigerant is a substitute of R22 refrigerant and is the most used refrigerant on the market. R410A refrigerant is a mixed refrigerant, which is a mixture of R32 (difluoromethane) and R125 (pentafluoroethane). The two substances are mixed in the ratio of 1:1.
As a substitute for R22 refrigerant, R410A has an ozone layer destruction potential (ODP) of 0 and will not destroy the ozone layer. However, the global warming coefficient (GWP) of R410A is 2025. Many people say R410A is an environmentally friendly refrigerant, but it is not! Although R410A does not destroy the ozone layer, it will produce greenhouse gases, and the greenhouse gas effect even partially exceeds R22.
R410A refrigerant is a mixture of two substances in a certain proportion. In case of leakage, the manufacturer recommends refilling, so as to ensure that the mixing proportion of the two substances is consistent.

3. R32 refrigerant
R32 refrigerant belongs to hydrofluorocarbons and its chemical name is difluoromethane. The ozone layer destruction potential (ODP) of R32 refrigerant is 0 as that of R410A, while the global warming coefficient (GWP) of R32 is only 675, which is far lower than that of R410A.
In addition, R32 refrigerant has higher performance, less injection volume and lower cost than R410A. Moreover, R32's working pressure and performance parameters are close to R410A, and its maintenance and installation are basically the same. Adding fluorine again is the same as that of R22. You can add as much as you need, and you don't need to empty it all and refill it again.
However, R32 has a disadvantage, that is, it is combustible, and the combustion grade is A2. This is undoubtedly the biggest stumbling block to the promotion of R32 refrigerant.

4. R290 refrigerant
R290 refrigerant is a more efficient and environmentally friendly refrigerant than R32 refrigerant. R290 does not belong to freon. Its chemical name is propane. Yes, it is the propane widely existing in natural gas. The ozone layer destruction potential (ODP) of R290 refrigerant is also zero, and its global warming coefficient (GWP) is very low, only 3.
It can be said that R290 refrigerant is the air conditioning refrigerant with the best environmental protection performance at present. However, R290 refrigerant is more flammable than R32, and its flammability is brought to grade A3. This puts forward higher requirements for all parts of the air conditioner, and it is required that the air conditioner can only be filled within 2p, and the air conditioner with large P number is limited. Therefore, this refrigerant has not been popularized at present. It is rumored in China that some manufacturers use R290 refrigerant for air conditioning products. It seems that some air conditioning products in Europe next door also use this refrigerant.

From the perspective of environmental protection, R32 and R290 refrigerants may be the most suitable refrigerants at present, but they are flammable and explosive! Some friends said, "environmental protection has nothing to do with me. I only care about safety."
Is that true? Let's look at the harm of excessive carbon emissions. Excessive carbon emissions will lead to global warming, produce greenhouse effect, accelerate the melting of ice and snow in the South and north poles, and cause the sea level to rise year by year; Cause extreme weather, such as typhoon, high temperature, rainstorm, debris flow, drought and other natural disasters; As a result, the temperature will rise, insect disasters will appear in some areas, the global food production may be seriously affected, and the output will gradually decline; The increase of carbon emissions will endanger people's health and quality of life. Who can survive the climate disaster?

As mentioned earlier, R32 refrigerant belongs to combustible substances. If combustible substances leak and encounter open fire, they will explode. At present, too many R32 air conditioning explosion accidents have been reported in the news. This undoubtedly makes consumers worried and afraid of R32 air conditioner, which has brought great obstacles to the renewal of air conditioning refrigerant.
R32 refrigerant is combustible. Combustion conditions: the concentration needs to reach a certain value and encounter open fire. The emergence of R32 air conditioner undoubtedly puts forward more standardized operation for air conditioner installers.

When installing the air conditioner, the length of the connecting pipe may be insufficient and the pipe needs to be lengthened. This situation is the most prone to problems and needs the most attention. First of all, the copper pipe should be lengthened, and the copper pipe needs to be reamed first. This step must be operated with a special pipe expander, and the hole must not be reamed with pointed nose pliers, so it is very easy to break and leak the copper pipe.
Another most important thing is the refrigerant leakage detection. Here, the refrigerant leakage detection steps in the Midea air conditioning manual are intercepted.

R32 product application precautions
1. If the copper pipe needs to be lengthened, the thickened copper pipe with thickness ≥ 0.8mm shall be used;
2. Pay attention to the difference between the installation and wiring and the pipe diameter of R22 refrigerant;
3. The internal machine and connecting pipe must be vacuumized and pressure maintained to ensure that the system has no leakage
4. Emptying is not allowed to replace vacuumizing;
5. For the extended copper pipe, add refrigerant according to the situation:
When the connecting pipe is less than or equal to 8m, no additional refrigerant is required. If the connecting pipe is more than 8m (subject to the liquid pipe), the refrigerant shall be added every 1m on the basis of 5m. The electronic scale must be used for quantitative addition. It is not allowed to add it by feeling or according to current, pressure and other parameters.