A refrigerant is a coolant that is essentially responsible for keeping the refrigerator cooler than the atmospheric temperature. Also, the properties of refrigerants substantially play an immense role in the proper functioning of a refrigerator and to the environment.
Over the decades, the evolution of refrigerant has changed from a fluorocarbon to a non-fluorocarbon refrigerant which is eco-friendly & environment-friendly doesn’t put a hole or produce harmful effects affecting the ozone layer.
The following are a few desirable characteristics of a refrigerant.
Easy leak detecting gases
On account of easy leak detection, gases like sulfur dioxide and ammonia are added to the refrigerant. In case of adverse leakage, they can be easily detected.
Red litmus paper test, chlorine test, ultrasonic and electronic leak detectors are few methods to find gas leakage effectively.
Global warming potential & ODP
GWP is the measure of how much heat a refrigerator produces and traps, which is usually calculated over a time period of 100 years. The estimated amount of GWP for Co2 and methane is around 1 and 72 for 100 years.
The rough estimate of the ozone layer depletion caused by the refrigerant is called Ozone Depletion potential (ODP). The ODP of R22 and R11 is fixed at 0.055 and 1.0.
Toxicity & Reactivity
Toxicity is the foremost important factor for a refrigerant. Under no circumstances should it inflict or become toxic to humans or turn the food poisonous.
A refrigerant, although used in a small amount in the cooling system of a fridge, must not react with the condenser or compressors, which might lead to corrosion and the slow death of the machine’s efficiency.
High vapor density & heat transfer coefficient
In order to use small compressor and condenser tubes, a refrigerant with a high vapor density is chosen, which requires a low specific volume; thus, it saves more space.
Likewise, if the heat transfer coefficient is high, it occupies less space and makes the system efficient, cost-effective, and compact.
High pressure & vaporization
Critical pressure of the refrigerant plays an important role in keeping the refrigerator cooling system properly functional. If the critical pressure is low, then the condensation would decrease, which in turn results in heat rejection in the system.
Higher latent heat vaporization is another factor to keep the mass flow rates under check. It is difficult to control the flow rates when the mass flow is really small; thus, higher heat vaporization helps predominantly.
Water solubility
Most of the refrigerants, when it comes in contact with water forms acids; this leads to corrosion of condenser valves, hermetic compressor pipes, and other metallic parts in the refrigerator. So having a low water solubility will increase the efficiency and life of the machinery.
Non-flammable
The refrigerant should not react with other gases in the air to make combustion. Ammonia in the air will create an explosive mixture in the air if the percentage of ammonia increases above 18% and higher.
Gases like So2, freon and other gases are Non-flammable when it mixes with the air. Whereas hydrocarbons and ammonia are highly flammable. So a refrigerant should always be Non-flammable.
Cost-effective
A refrigerant is used in very small quantities, and it’s preferred to have a high-quality refrigerant which is a pinch on the expensive side. Still, in the case of cheap refrigerant, they might lead up to leakages, and you might want to run to a nearby maintenance store to schedule a fix.
Final takeaway
A refrigerant plays an essential role in the proper functioning of a refrigerator, it should not only possess the above characteristics, but it should also be environment-friendly to the atmosphere. Hence the evolution of refrigerant keeps happening to upgrade the existing refrigerant with the new refrigerant for better performance and less harmful to our environment.