Each house has household appliances, for the production and operability of which a substance such as freon is used. This substance, known as an excellent refrigerant, is used in all refrigerators, due to which it is possible to store foods and prepared meals for a longer period than at ambient temperature. This article will tell you that freon is what kind of substance it is, where it is used, what temperature it has.
Discovery story
Various sources call the two dates of the first synthesis of freon - 1928 and 1931. It is more correct to consider the date of birth of this refrigerant as 1928. It was then that the company's outstanding chemist Frigidaire, which is a subsidiary of General Motors, Thomas Midgley, introduced the "miracle substance" and gave it the name "Freon." Later, engineers of the company engaged in the industrial production of this gas introduced the designation Freon-12 as "R" (in the translation "Refrigerant" stands for refrigerant or cooler). The second date with the appearance of Freon is not right to associate, since already in 1930 the Kinetic Chemical Company was established, the activity of which was to be directed to the production of this product.
Freon - what is it?
A mixture of ethane and methane as fluorine-containing derivatives of low molecular weight hydrocarbons, where hydrogen atoms can be replaced by fluorine, chlorine, bromine. Widely used in refrigeration units (refrigerators, freezers, air conditioners, etc.). Many people wonder, is freon a gas or a liquid? The correct answer: this substance can have both aggregate states.
The most common types of freon
Science knows more than 40 types of this substance, most of which are obtained industrially. The temperature of freon, at which it boils, each species has its own:
- R11 - trichlorofluoromethane (with a boiling point of 23.8 ° C).
- R12 - difluorodichloromethane (with a boiling point of bale –29.8 ° C).
- R13 - trifluorochloromethane (with a boiling point of bale –81.5 ° C).
- R14 - tetrafluoromethane (with a boiling temperature of –128 ° C).
- R134A - tetrafluoroethane (with a boiling point of bale –26.3 ° C).
- R22 - chlorodifluoromethane (with a boiling point of –40.8 ° C).
- R600A - isobutane (with a boiling point of –11.73 ° C).
- R410A - chlorofluorocarbonate (with boiling point –51.4 ° C).
As a rule, home refrigerators operate on R-22 brand freon (freon) , and R-13 brand is used in industrial and commercial ones.
Is Freon a dangerous substance for humans?
Almost all types of this substance have a negative boiling point, which is why it is used in cooling elements of household appliances, as a pushing element in gas cartridges, air fresheners and other aerosols. Therefore, when spraying the cylinder itself is cooled, and freon enters the air. If the refrigerant is not heated to 250 degrees (toxic substances are released at this temperature), it is completely harmless to humans, which cannot be said about the ozone layer. Decay products destroy it. The main reason for the formation of ozone holes is the production and use of freon with a high content of chlorine and bromine ions. The leak of this substance in household appliances cannot be visually detected on the smell, small doses on a person do not have any effect.
To restore the ozone layer of the Earth and reduce the production of harmful freons, the UN countries signed and ratified the Montreal Protocol.
What is freon in refrigeration units?
Modern compressor refrigerators are presented in the form of a chamber with an evaporator located inside, which includes refrigerant. This substance, when boiling and evaporating, takes heat from the chamber and transfers it to the environment during condensation. Due to this, the air is cooled to the required temperature, and the gas returns to the compressor and changes its state of aggregation to liquid. Freon in the refrigerator is located in this evaporator. In other words, this is an important component of the system, due to which the cooling chambers of the refrigeration unit are cooled.
How to understand about the leak of freon from the refrigerator
It is clear that this substance is one of the main components of the proper operation of technology. Leakage of freon leads to damage to the equipment and the inability to use it for its intended purpose. The most common cause of this problem is damage to the evaporator pipe or factory defect. Since it is an odorless volatile gas, it cannot be detected by olfactory receptors.
However, there are some signs by which a leak can be identified. Freon in the refrigerator is under pressure, and when the evaporator tubes are damaged, it gradually begins to fall. As a result, the air temperature rises in the refrigerator and freezer, and the products are quickly deteriorating. This is the first sign that it is necessary to check the integrity of the cooling system of the device. As mentioned earlier, freon is not dangerous for humans at temperatures not exceeding 250 degrees, and it is impossible to heat it to such a temperature at home.
Most common refrigerant leaks
First of all, these are pipe joints. In any soldering, microcracks can form both due to the long operation of the equipment, and as a result of factory defects. Also, a freon leak is often found in the places of the connecting tubes of the evaporator of the refrigerating and freezing chambers. Sealing can also be detected on the return line, which connects the heart of the refrigerator and the evaporator.
How to repair a leak?
Filling a freon refrigerator at home without the help of a professional is impossible. Since for this work special equipment and materials will be needed (vacuum pump, soldering torch, batcher, manifold with pressure gauges, metal for solder, special flux). To detect a leak in the tubes, a special device resembling a metal detector is used. After the master detects the place of damage and seals this area, eliminating the leak, the remaining gas is pumped out with a vacuum pump and refilled. Filling takes place by attaching a gas cylinder to the fitting located on the casing of the compressor of the refrigerator, through a capillary tube, the connection is made with a tight wrench.
After this, the freon in the refrigerator again begins to circulate properly, and the temperature in the chambers is set in accordance with the standards for refrigeration devices.