Did you know this: Gas or Refrigerant is responsible for keeping the air in your refrigerator cool?
Totally unexpected, isn’t it! Yes.
From mini-refrigerators to double-door fridges to a freezer, all of them have a refrigerant gas that helps in maintaining cool temperatures within.
If you are unaware of what a refrigerant gas is and its significance, keep reading below.
This article will shed some light on the role of refrigerant, and also different types of gases used in the refrigerator.
What is a Refrigerant?
A refrigerant is a liquid or fluid used in a refrigerator to absorb heat from the environment and remove it to another. It provides refrigeration or air conditioning, and you often find them in air conditioners and freezers.
Earlier, the refrigerators had Hydrofluorocarbons (HFC), Chlorofluorocarbons (CFC) as refrigerants. These chemical coolants posed a serious threat to ozone depletion and hence got rejected or invalidated eventually.
Now that we know what a refrigerant is let us now try to understand how it works in the refrigerator.
How Does Refrigerator Work?
Refrigerant gas plays a crucial role in the functioning of refrigerators. The refrigerant gas undergoes a series of evaporation (liquid to gas) and condensation (gas to liquid) processes. During this cycle, it pulls out the heat, keeping the temperature inside the fridge chill.
Let me help you understand it better. We all know that the primary job of a refrigerator or any cooling device is refrigeration. That means it should keep the objects inside the fridge cool, and this is achievable only when there is a cold liquid passing continuously around the object.
We will be talking about two crucial components of a refrigerator, i.e., a throttling device and a compressor.
A throttling device is a simple device located at the heart of the refrigerator. However, in most fridges, a capillary tube works as a throttling device.
The refrigerant in its liquid state passes through this throttling device or capillary tube. This device hinders the flow, thereby causing an enormous drop in the pressure. Due to this pressure drop, the refrigerant boiling point decreases, and it starts evaporating.
Since the heat required for evaporation comes within the refrigerant, its temperature also comes down.
The next phase in the refrigerant cycle is to pass this cold fluid over the object that needs heat absorption. During this heat absorption process, the refrigerant further evaporates and converts into pure vapor. This process successfully generates the refrigeration required for the refrigerator.
To repeat this process over and again, this low-pressure vapor refrigerant should go back to the previous state. That means it should get back to the high-pressure liquid state which was before entering the throttling device.
This is when the compressor of the refrigerator comes into play. The compressor increases the pressure back to its initial value. However, it compresses gas along with pressure and hence increases the temperature as well. This is inevitable.
Now, the refrigerant reached back to high-pressure vapor. The next step here is to convert it to the liquid state again, and you need another heat exchanger for this. You can find this heat exchanger fitted outside the refrigerator. This will release the heat to the surroundings, causing the vapor to get condensed to liquid. Eventually, the temperature will drop down to a normal level.
The refrigerant is now back to its initial state again, which is the high-pressure liquid. This is a cycle that repeats over and over for continuous refrigeration and hence called the vapor compression cycle.
What are the Types of Refrigerants or Gas used in Refrigerators?
Initially, from 1800-1920, refrigerators had toxic gases, a mixture of chlorine, fluorine, and carbons. However, after discovering that these were harmful to the atmosphere, they got phased out around 1970.
These gases would contribute to ozone depletion and the greenhouse effect. Hence, they started using refrigerant gases that were a combination of hydrogen, chlorine, fluorine, and carbons like HCFC and HFC.
HCFC or R-22
HCFC or Hydrochlorofluorocarbons are gases that have a very minimal impact on the ozone layer and its depletion. Their lifespan decreases after getting exposed to the atmosphere. The most common HCFC used as a refrigerant is R-22.
HFC or R-134A
HFCs (Hydro Fluro Carbons) are another set of refrigerants that do not contain chlorine. Though they are potent greenhouse gases, they are much better than HCFCs, as they have zero potential for ozone depletion.
R-134A or R438A is the most commonly used HFC in refrigerators, which is better than R-22.
Isobutane or R-600A
The HCs (hydrocarbons) that are currently available in the Indian market are R-290 and R-600A. These are the most environment-friendly refrigerants. Propane is the chemical name for R-290, and Iso-Butane is the chemical name for R-600A
The best thing about these refrigerants is that they are halogen-free. They are increasingly popular because of their zero-ozone depletion potential and low global warming potential. These refrigerants are high-energy efficient and highly flammable, too. They are possible replacements for other refrigerants in the market and often termed as the greenest refrigerants.
- R22 Chlorofluorocarbons– A commonly used gas in the older refrigerator that got phased out because of its ozone-depleting nature. You will not see it in the modern fridge.
- R134A Tetrafluoroethane– You can see this gas in current refrigerators. It is an ozone-friendly and potent greenhouse gas, too. Hence, this might as well get phased out soon. However, it is still the preferred choice.
- R438A Freon– Used as a replacement for R22, this gas is non-ozone depleting. You can find it in most refrigerators today and also in the older ones (repaired) that were earlier using R-22 gas
- R600A Iso Butane– It is a very efficient refrigerant commonly used in small modern fridges. It is a flammable gas, too.
Frequently Asked Questions
Ans. When the fridge gas or refrigerant starts running out, you will notice blocks of ice building up – the food and other items, including milk and eggs freeze. You will also observe a moldy smell inside the fridge with the accumulation of ice.
The replacement cost of a refrigerant may range from Rs 600 to 1000. However, it may vary depending on the refrigerant gas used to refill.
Ans. Refrigerant gas plays a vital role in keeping the inside material fresh and cool, insufficient refrigerant level could starve the units of the fridge resulting in odor and material mar.
Ans. The average life expectancy of refrigerants is 12-16 years.
Ans. In modern refrigerators, Tetrafluoroethane R-134a, and Freon R-438A are the most common refrigerant gas used in India.
Ans. Refrigerant poisoning is quite a serious problem and could affect your health. Headaches, difficulty in breathing, coughing, nausea, vomiting, irritation in the eyes, and skin are some common conditions that you could get into. The refrigerant gas is of a chemical nature which means you should not be careless in their presence.
Ans. It is best to call for a professional technician for filling the refrigerant gas as the task is a bit complicated and lengthy. However, if you want to DIY, you can go ahead. There are many online tutorials to learn this process and apply it practically. Stay careful though!
I hope this article answered all your questions about refrigerant gas and how it helps in refrigeration.
Now that you have a fair idea of the gases used in the fridge, try opting for a refrigerator with R-600A.
At least, try getting it refilled with R-600A, as it is environmental-friendly.
Let us know in the comments section below about what you think of this article.