In the last several weeks, I’ve posted a lot of information about air conditioner efficiency, and how to keep your air conditioner running well over time. I’ve also posted information about the rising cost of recharging older air conditioning units that use a refrigerant known as R-22. While it’s easy to find arguments on both sides of the question about the efficiency and desirability of R-22 as a refrigerant, it’s not always so easy to understand why R-22 is being taken off the market.

R-22 falls into a class of refrigerants that has been identified as harmful to the Earth’s ozone layer. The largest known “hole” in the Earth’s ozone layer is concentrated over Antarctica. Certain chemicals, known as halogenated hydrocarbons, deplete the ozone layer and decrease the protection the Earth’s atmosphere offers against solar radiation.

In 1987, many countries began to sign on to a global treaty called the “Montreal Protocol On Substances That Deplete The Ozone Layer,” referred to in short as “the Montreal Protocol.” This treaty aims to phase out the use of chlorofluorocarbons (CFC) and hydrochlorofluorcarbons (HCFC), to prevent harmful substances from entering the ozone layer. R-22 is considered a HCFC.

As of 2010, manufacturers may not ship new air conditioning units that are charged with new R-22 refrigerant. New R-22 is still available as a recharge refrigerant for existing units. Manufacturers are skirting this portion of the agreement by shipping “dry-charged” units, or units filled with nitrogen instead of R-22. Once the unit is installed, the installer “re-charges” the unit with new R-22. By 2020, however, even recharging with R-22 will be limited to the use of recycled or reclaimed R-22, and no new R-22 will be manufactured anywhere.

So, what is the current alternative to R-22? A refrigerant known as R-410a is currently used as a substitute for R-22. R-410a works at a higher pressure than R-22 does, and it isn’t possible to use R-410a as a direct substitute for R-22. In other words, if your air conditioner was designed to work with R-22, you can’t simply recharge the unit with R-410a instead.

R-410a is also classified as a HCFC, but unlike R-22, it doesn’t have the same ozone-depleting consequences that R-22 does. Unfortunately, R-410a does contribute to global warming, so the plan is to eliminate R-410a from use with other HCFCs, according to the timetable established by the Montreal Protocol.
Consumers should be aware that air conditioners have become a lot more efficient in the last 10 years. Replacing an older air conditioner that is still in good working condition might make economic sense when the replacement unit is significantly more efficient than the existing one. Consumers will need to factor in the cost of recharging (which will become significantly more expensive as R-22 supplies decline) an existing air conditioner when considering possible replacement. Additionally, it will become harder to replace older, R-22 units over time as more manufacturers adopt R-410a designs.

Fortunately for consumers, R-410a performs about as well as R-22 does in most circumstances, including those typically encountered in Boston. In any case, consumers should work only with certified technicians when it comes to recharging air conditioner units and recovering R-22 refrigerant.

If you would like more information about air conditioners, air conditioner maintenance, recommendations, or you would like to have your own air conditioning system cleaned and prepared for use this season, give Boston Standard Plumbing & Heating a call at (617) 288-2911, and we’ll schedule an appointment. Don’t forget to like Boston Standard Plumbing on Facebook!