組件/設計差異
在汽車空調系統中壓倒性地選擇R-1234yf來替代R-134a的一個令人信服的原因之一是，因為系統的設計和工作方式之間并沒有太多差異。熱力膨脹閥（更換節流孔管或膨脹閥）和冷凝器有幾處較小的組件更改，但總體而言，從事A / C系統工作的任何人都將熟悉該系統。兩個系統中的服務端口都是快速連接的，但是在yf系統中它們較高，以避免交叉污染。
另一個區別是 R-1234yf蒸發器必須符合SAE Spec J2842，這在R-134a系統中不是問題。最后的區別是，大多數（盡管不是全部）R-1234yf汽車都將配備吸氣管熱交換器。該零件是生產線組件的一部分，旨在提高效率。它們沒有活動部件。
工作壓力/溫度差異
R-1234yf和R-134a的壓力/溫度曲線非常相似。如下圖所示，下面的曲線幾乎一起貫穿整個曲線，僅在250 psig / 150度及以上時略有斷開的路徑
易燃/安全
R-1234yf被為輕度易燃。這僅表示如果與明火接觸可能會燃燒。重要的是要注意它確實具有低燃燒速度和低熱量或燃燒性。它的壓力上升非常低，火焰移動非常緩慢（小于10厘米/秒）。與商店中的其他液體/化學品/氣體相比，它是一種極其緩慢的移動火焰。它在車輛中的體積小，撞擊性低。相比之下，如下表所示，它具有以下幾種常見的汽車油：汽油，柴油，發動機油，變速箱油和動力轉向液的可燃性影響更低。
R1234YF制冷劑是一種無臭氧層破壞性且低變暖潛值(GWP）的車用空調制冷劑,符合歐盟汽車空調(MAC指令）,該指令旨在逐步停止高GWP制冷劑在汽車空調中的使用。 R1234YF的GWP<1根據AR5,完全符合歐盟MAC指令。 R1234YF表現出與R-134a相似的操作工況,可以在所有允許使用微弱可燃工質的場合替代R134a。R1234YF的安全分類為微弱可燃（A2L）,但如需在直膨式汽車空調系統中使用,僅需要適度地改變設計。
文章英文原文：
One of the compelling reasons R-1234yf was overwhelmingly chosen to replace R-134a in automotive air conditioning systems is because there are not really many differences between the way the systems are designed and work. There are a couple minor component changes in the Thermal Expansion Valves (replace orifice tubes or expansion valves) and Condensers, but overall the system will be familiar to anyone who works on A/C systems. The service ports in both systems are quick-connect, but they are taller in the yf systems to avoid cross-contamination.
Another difference is that yf Evaporators must meet SAE Spec J2842, which was not an issue in R-134a systems.
A final difference is that most (though not all) R-1234yf cars will have a Suction Line Heat Exchanger. This part is part of the line assembly and is designed to improve efficiency. They have no moving parts.
Operating Pressure/Temperature Differences
The pressure/temperature curves for R-1234yf and R-134a are very similar. As illustrated in the chart below, the curves below run together nearly throughout the curve, only slightly breaking paths at around 250 psig/150 degrees and above
Flammability/Safety
R-1234yf has been designated as MILDLY flammable. This simply means that it could ignite if it comes in contact with an open flame. It is important to note that it does have a low burning velocity and low heat or combustion. It has a very low pressure rise and the flame is very slow moving (less than 10cm/sec.) Compared to other liquids/chemicals/gases in a shop, it is an EXTREMELY slow moving flame. It has low volume in a vehicle, and low impact flammability. By comparison, and as illustrated in the chart below, it has the significantly lowest flammability impact of the following common automotive fluids: gasoline, diesel, engine oil, transmission fluid, and power steering fluid.
