Automotive R-134A Air Conditioning 101. How To Add Refrigerant And Check Pressures

[@deankay4434]

Curt, Fast down and accurate info on A/C systems. For you folks doing a resto-mod from R12 to R134a, just remember that R134a carries more BTU’s of heat energy that R12. R12 boil at a lower temp than R134a, thus requiring less charge than the under hood sticker shows. Say an R12 system holds 2.0lbs of refrigerant but you install R134a adapters and used bought a manifold set and newer A/C condenser in front of the radiator or a salvage yard unit exactly the same, make to blow freely thru a used condenser as it has thin match book sized tubes. These are extruded with 8-10 square hole and have greater efficiency to remove latent heat. (What is Latent heat? It like boiling water on stove. It hits 212 F, but no bubbles. 570 BTU’s have to be added to change that liquid into a gas, or steam) Same with A/C as hot refrigerant has heat to be removed from the condenser to change from a hot gas to a liquid! This is not magic, just physics but new condensers no longer have round tubes to pass a bee bee from inlet to outlet. In short, new condensers are way more efficient than old. Lube all O-rings with mineral oil or R12 lube as it doesn’t attract moisture into the fitting causing it to guald or glue up and seize up. Use green O-rings to seal. Never use R134a lube to coat a fitting with O-ring as this attracts moisture into fitting. You will find this in salvage yards of harvesting a part. Threads come off. To charge a converted R12 system to R134a, use formula R12 X 0.9 = charge - 0.25lbs. Less refrigerant for better results and higher cooling capacity! ASE Master 78. Thank you kindly Curt for your video information!😊 (A couple of typo corrections made)