Before we get any further into our chat about the phaseout, I think it’s worthwhile and only fair to point out that Freon is not some evil substance that we must panic and eradicate immediately. As long as your air conditioner is still operating and you aren’t experiencing problems with it, you don’t need to do anything whatsoever with this information except file it away for your future reference, or maybe use it to amaze your friends at cocktail parties with what a smarty-pants you are about global environmental science. So let’s get started with today’s history/chemistry lesson, shall we?
Chlorofluorocarbons (CFC’s) were a scientific breakthrough, and they were developed in the 1930’s as less toxic, less flammable, and generally non-reactive alternatives to substances that were previously used for fire suppression, refrigeration, and propellants. For all of these reasons, they became very popular, and I don’t think it’s a big stretch to say that we owe a lot of our home comfort to their development. But even though they are safer than their predecessors, it turns out that they created an entirely different problem when they began to build up in the atmosphere.
The problem starts when ultraviolet rays break off individual chlorine atoms, who become our atmospheric bullies. Chlorine starts floating around, and sees a three-atom ozone molecule hanging out, talking about their totally awesome band called O3. Chlorine busts in and grabs the keyboard player. The singer and the drummer take off, and since they didn’t need that guy to make it big anyway, they leave poor Atom in the clutches of Chlorine. Eventually Atom’s dad shows up, and Chlorine has to pretend nothing’s happening and let him go. So now instead of one O3 molecule, we have two O2 molecules, and Chlorine is roaming around loose again, and I bet you can guess what happens next, right? Yup, it starts all over again. Just one atom of Chlorine can repeat this cycle thousands of times.
Scientists started noticing something happening to the ozone back in the 1970’s, and by the 1980’s had collected enough evidence to sound the alarm. The discoveries and research of scientists who were attempting to prove or disprove the effects of ozone depletion fueled the global discussion that led to the Vienna Convention and the Montreal Protocol (more on that another day). And while the politicians tackled the problem from one angle, the scientists were left with another big question: “If we get rid of CFC’s, what happens to all of those many, many products that use them?”
And of course, where there is adversity, there is opportunity. Enter Puron, or R-410A. Just like CFC’s were developed as a step forward from earlier harmful substances, R-410A is the step forward from R-22 in the air conditioning field. It is a hydrofluorocarbon (HFC) instead of a CFC, so it doesn’t unleash those nasty chlorine atoms on us. R-410A will serve the same function in your air conditioner that R-22 did, but the chemical differences between the two substances mean that they’re not interchangeable. You can think of the difference as making a salad dressing of oil and vinegar – although they’re both liquids serving the same purpose, they want to get as far away from each other as possible as soon as they get the chance.
For as long as your R-22 system is working well for you, this can all go under the heading of Good to Know. There’s a good reason there are so many R-22 systems out there, and now you know a little bit more about why. So give yourself a pat on the back, you just got an A in today’s History/Chemistry class – go you!
– Shanna