Every home has household appliances, for the production and operation of which a substance such as freon is used. This substance, known as an excellent refrigerant, is used in all refrigerators, thanks to which it is possible to store food and prepared meals for a longer period than at ambient temperature. This article will tell you what freon is, what kind of substance it is, where it is used, what temperature it has.
Discovery history
Different sources give two dates for the first freon synthesis - 1928 and 1931. It is more correct to consider the year 1928 as the date of birth of this refrigerant. It was then that the outstanding chemist of the Frigidaire company, which is a subsidiary of General Motors Corporation, Thomas Midgley, brought out the “miracle substance” and gave it the name “freon”. Later, the company's engineers involved in the industrial production of this gas introduced the designation Freon-12 as "R" (in translation, "Refrigerant" stands for refrigerant or cooler). The second date fromIt is wrong to associate the appearance of freon, since already in 1930 the Kinetic Chemical Company was established, whose activities were supposed to be aimed at 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 applications (refrigerators, freezers, air conditioners, etc.). Many people ask the question, is freon a gas or a liquid? Correct answer: a given substance can have both states of aggregation.
The most common types of freon
Science knows more than 40 types of this substance, most of which are obtained industrially. Freon temperature, at which it boils, each type has its own:
- R11 - trichlorofluoromethane (with a boiling point of 23.8 °C).
- R12 - difluorodichloromethane (bp -29.8 °C).
- R13 - trifluorochloromethane (bp -81.5 °C).
- R14 - tetrafluoromethane (boiling point -128 °C).
- R134A - tetrafluoroethane (bp -26.3 °C).
- R22 - chlorodifluoromethane (bp -40, 8 °C).
- R600A - isobutane (bp -11.73 °C).
- R410A - Chlorofluorocarbonate (Bp -51.4°C).
As a rule, home refrigerators run on freon (freon) brand R-22, in industrial and commercial use brand R-13.
Freon is a dangerous substance for humans?
Almost all kinds of this substancehave a negative boiling point, which is why it is used in the 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. The 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. A leak of this substance in household appliances cannot be smelled or visually detected, small doses have no effect on a person.
To restore the Earth's ozone layer 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 placed inside, which includes a refrigerant. This substance, when boiling and evaporating, takes heat from the chamber and, in the process of condensation, transfers it to the environment. 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 just in this evaporator. In other words, this is an important component of the system, due to which the cooling of the refrigeration chambers takes place.installation.
How to understand about the leakage of freon from the refrigerator
It is clear that this substance is one of the main components of the correct operation of equipment. Freon leakage leads to a breakdown of equipment and the inability to use it for its intended purpose. The most common cause of this problem is damage to the evaporator tube or a factory defect. Because it is a volatile, odorless 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 begin to deteriorate quickly. This is the first sign that you need to check the integrity of the instrument's cooling system. As mentioned earlier, freon is not dangerous for a person at a temperature not higher than 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 due to factory defects. Freon leaks are also common in the places of the connecting pipes of the evaporator of the refrigerator and freezer. The seal can also be found on the return line that connects the heart of the refrigerator and the evaporator.
How to repair a leak?
Refillrefrigerator freon at home without the help of a professional is impossible. Since this work will require special equipment and materials (vacuum pump, soldering torch, dispenser, manifold with pressure gauges, solder metal, special flux). To detect a violation of the tightness of the tubes, a special device resembling a metal detector is used. After the master identifies the place of damage and seals this area, eliminating the leak, the remaining gas is pumped out with a vacuum pump and refilled. Filling occurs by connecting a gas cylinder to the fitting located on the casing of the refrigerator compressor through a capillary tube, the connection is made with an airtight key.
After that, the freon in the refrigerator starts to circulate properly again, and the temperature in the chambers is set in accordance with the standards for refrigeration devices.
