Author: Gerson Mora

We will conduct a comparison between two refrigerant gases: R22 and its replacement, R417A.

• Before delving into the details, it’s essential to highlight that R417A is a replacement gas for R22, specifically designed for medium and high-temperature applications such as refrigeration and air conditioning. It is also suitable for heat pump systems that previously used R22.
• Regarding their composition, R22 is internally composed of a single component without any gas mixture, allowing it to be charged in either liquid or gaseous phase.
• On the other hand, R417A, also known as Isceon 59, is a gas mixture consisting of 50% R-134a, 46.6% R-125, and 3.4% R600 Butane. Due to this composition, R417A must be charged in its liquid phase.
• The main drawback of R22 is its detrimental impact on the ozone layer, leading to severe environmental restrictions on its usage. In contrast, R417A (Isceon 59) does not harm the ozone layer. However, its high Global Warming Potential (GWP) of 2346 makes it subject to environmental restrictions in certain regions, limiting its market usage in the short term.
• Both R22 and R417A are compatible with mineral oils and alkylbenzenes, meaning that when switching from R22 to R417A, there’s no need to change the compressor oil.
• An additional advantage of this change is that no equipment components need to be replaced.
• While there might be a slight decrease in the cooling capacity of the system when using R417A, this difference is imperceptible. Moreover, this new cooling capacity results in lower electricity consumption compared to R22.
• Both R22 and R417A are safe to use, as they are non-toxic and non-flammable.

We are going to develop a comparison between TWO refrigerant gases. We’re talking about R404A and its substitute, gas R448A.

• Let’s start by saying that both R404A and R448A are internally composed of a mixture of several gases, which is why both should always be charged in liquid phase.
• For example, R404A contains approximately 4% R134A, 44% R125, and 52% R-143A.
• Meanwhile, refrigerant gas R448A is composed of a mixture of gases as follows: R32 (26%), R1234ze (7%), R134a (21%), R125 (26%), and R1234yf (20%).
• The glide of R404A is very low and lower than that of R448A. Remember, glide is the temperature change of the gas during phase transition.
• Neither R404A nor R448A damage the ozone layer.
• R448A has a global warming potential (GWP) of 1387, while R404A has a GWP of 3920. It is precisely this high GWP value that condemns the use of R404A due to environmental restrictions.
• R448A is considered a replacement refrigerant for R404A in low and medium-temperature applications in the evaporator.
• The change from R404A to R448A does not require any modification in the compressor because the discharge temperature of the R448A is very similar to that of R404A.
• R448A is a perfect substitute because it works just like R404A with POE-type oil.
• R448A is compatible with the components and seals of an existing R404A installation.
• Both R404A and R448A are gases with a safety classification of A1, group L1, meaning they have low toxicity and are not flammable.

In this post, we are going to conduct an interesting comparison between the refrigerant gases R134a and R600a. So get ready to discover the differences between them!.

• Let’s start by saying that R600a and R134a are pure gases that can be recharged in both liquid and gaseous phases since they are not composed of gas mixtures.
• R600a is a hydrocarbon used as a refrigerant, mainly in domestic refrigerators.
• On the other hand, R134a is used in equipment of any power, such as domestic and commercial refrigerators, chillers for building air conditioning, chillers for machine cooling, and automotive air conditioning systems.
• The main advantage of R600a is its low environmental impact and excellent thermodynamic properties, which contribute to its increasing use.
• R600a does not harm the ozone layer and has a Global Warming Potential (GWP) of 3.
• On the other hand, R134a also does not harm the ozone layer but has a GWP of 1430, which, over the years, is starting to face challenges with stricter environmental regulations.
• R600a (isobutane) has a safety classification of A3 – non-toxic but flammable. R134a is non-toxic and non-flammable.
• Although R600a (isobutane) is flammable, its use in refrigeration systems with lower cooling capacity reduces the risk due to the significantly low amount of R600a refrigerant used.
• Isobutane R600a, like other hydrocarbon refrigerants, generally has good miscibility with any type of lubricant, although in many cases, it is recommended to use oils with higher viscosity.
• R134a is compatible with POE oil in conventional refrigeration and PAG oil in automotive air conditioning.
• R600a has proven to reduce the energy consumption of refrigeration systems compared to R134a.
• R600a and R134a are not direct substitutes for each other in equipment that has already been used, unless authorized by the manufacturer. However, if R600a is replaced by R134a, the capillary must be changed because the displacement of the compressor with R600a is higher than with R134a.

Welcome to this post where we’ll embark on an intriguing comparison between the refrigerants R134a and R290. Brace yourselves to uncover the fascinating differences between these two!

• Let’s start by emphasizing that both R290 and R134a are pure gases, capable of being recharged in either liquid or gaseous phase since they are not composed of gas mixtures.
• Propane, or R290, serves as a hydrocarbon refrigerant primarily used in domestic refrigerators, small commercial cooling devices, as well as in low-power air conditioning units and heat pumps. Meanwhile, R134a finds use in equipment of any power range, including domestic and commercial refrigerators, air conditioning chillers for buildings, machine cooling chillers, and automotive air conditioning systems.
• The primary advantage of R290 lies in its low environmental impact and excellent thermodynamic properties, making it increasingly favored in various applications. R290 is ozone-friendly and boasts an impressively low Global Warming Potential (GWP) of only 3.
• On the other hand, R134a also doesn’t harm the ozone layer but has a relatively higher GWP of 1430. As the years pass, this poses challenges due to more stringent environmental restrictions.
• R290 propane carries a safety classification of A3, being non-toxic but extremely flammable. In contrast, R134a is non-toxic and non-flammable.
• Although R290 propane is flammable, the risk is reduced since it is primarily used in cooling circuits with lower cooling capacities, resulting in notably lower quantities of the refrigerant being present.
• Moreover, R290, like other hydrocarbon-type refrigerants, exhibits excellent miscibility with any type of lubricant, although it is recommended to use lubricants with higher viscosity levels. R134a, on the other hand, is compatible with POE oil in conventional refrigeration and PAG oil in automotive air conditioning systems.

• R290 has demonstrated a remarkable reduction in energy consumption in refrigeration systems when compared to R134a.

• Furthermore, it’s crucial to note that R290 and R134a are not interchangeable gases in systems that have already been in operation, unless explicitly authorized by the manufacturer. Using R290 in systems not designed for this gas can lead to instability and adversely affect the compressor’s lifespan.
• DO NOT SUBSTITUTE ONE GAS FOR ANOTHER.
• For instance, for a refrigeration unit operating at -10°C, an absolute pressure of 29.4 psi is obtained from the table. The atmospheric pressure should be subtracted from the table value, for example:

Gauge Pressure = Absolute Pressure – Atmospheric Pressure (14.7 psi)

Gauge Pressure = 29.4 psi – 14.7 psi = 14.7 psi

The pressure-temperature charts for R290 (propane) in gauge pressure do NOT REQUIRE CALCULATIONS, as they provide direct values, using an atmospheric pressure reference of 14.7 psi.

We will develop a comparison between TWO refrigerant gases with serious ecological issues. We’re talking about R404A and R22.

• R22 destroys the ozone layer and has a global warming potential (gwp) of 1760, while r404a does not deplete the ozone layer but has a gwp of 3922
• R22 is a pure refrigerant, meaning it is composed of a single gas. On the other hand, R404A is internally formed by a mixture of several gases.
• R22 is used in various fields, including air conditioning, refrigeration, and freezing, while R404A is mainly used for freezing and with less efficiency in refrigeration. It is not used in air conditioning.
• Both R22 and R404A are non-toxic and non-flammable.<break time=”2s”/>
• In the case of R22, it is possible to recharge it in both liquid and gaseous phases without any problem due to its nature as a pure refrigerant. However, R404A, being a gas mixture, must always be recharged in the liquid phase. This is an important consideration to take into account when performing maintenance on refrigeration systems.
• Furthermore, it’s interesting to know the internal composition of R404A. This refrigerant contains approximately 4% of R134a, 44% R125 gas, and 52% R32
• Another significant difference between the two gases is their compatibility with different types of oil. R22 is compatible with mineral oil and alkylbenzene but not with POE oil.
• On the other hand, the refrigerant gas R404A is only compatible with POE oil.
• Although R404A and R22 have a similar cooling performance, there are still many differences between them in real-world use.
• The saturation pressures of R404A and R22 are different at the same temperature, making them not interchangeable.
• If you replace R22 with R404A, problems may arise with the operation of the expansion valve, pressure control, lubrication, accumulators, separators, and refrigerant gas flow.
• Additionally, since the density of R404A gas is approximately 50% higher than that of R22, using R404A requires a larger pipe diameter for the same displacement.
• Let’s examine the differences in the measurements of the capillary tube for both refrigerant gases under the same operating condition.
• For the same compressor, the current required for R404A is higher than that for R22.

We are going to develop a comparison between the refrigerant gases R134a and one of its substitutes in the new automotive air conditioning systems, which is R1234yf.

• R1234yf is a substance remarkably similar in cooling performance to its predecessor, R134a, while having a Global Warming Potential (GWP) of 1 compared to the GWP of R134a, which is 1430.
• Both R134a and R1234yf are pure refrigerants, meaning they are composed of a single gas. Therefore, both R134a and R1234yf can be recharged in both liquid and gas phases without any issues.
• R1234yf requires specific PAG, PVE, and POE oils designed for this gas. It’s important to ensure that the oil used is compatible with R1234yf.
• R1234yf is highly corrosive, so only clean and properly specified lubricants can protect the system.
• R134a uses POE oil in conventional refrigeration and PAG oil in automotive air conditioning.
• R1234yf has low toxicity, is slightly flammable, and shows excellent compatibility with most materials. It is classified as A2L, group L2 in terms of safety. Similarly, R134a is non-toxic, non-flammable, and classified as A1, L1.
• In addition to the automotive sector, both R134a and R1234yf are used in chillers for air conditioning in buildings and machine cooling.
• Vehicles using R1234yf have different service fittings compared to vehicles using R134a to prevent cross-contamination with different refrigerants. For example, adapters are required to connect pressure measurement gauges.
• R1234yf is more expensive than R134a.
• It is not recommended to change from R1234yf to R134a for legal reasons.
• Although the system may operate and cool when switching from R1234yf to R134a, its performance and capacity will be affected, and some inconveniences may arise, which we will discuss next.
• R1234yf systems that control freeze protection by pressure may lose cooling performance if charged with R134a. This is due to the lower adjustment requirement of R134a.
• Mixing R134a with R1234yf will alter the refrigerant pressure and may result in evaporator freezing in pressure-controlled systems, reducing the airflow.
• The expansion valve setting for R1234yf refrigerant is different compared to R134a. Changing from R1234yf to R134a may result in a system with incorrect refrigerant flow and heat exchanger mal-distribution, leading to a loss of cooling performance or durability issues.
• Changing from R1234yf to R134a can result in an increase in suction line pressure drop, reducing the efficiency of the equipment. This can be particularly damaging in the case of dual evaporator systems.