A Brief History of Refrigerants

What makes a good refrigerant anyway? It all starts with having the right boiling point (BP.)  Heat flows from hot to cold, and when heat is removed (from a home or refrigerator), it gets added to the refrigerant in the evaporator.  When heat is added to liquid refrigerant, it rises in temperature until it reaches the BP and only gas remains.  The BP of the refrigerant must be significantly lower than the desired conditioned space temperature.  Other factors for what make a good refrigerant are environmental effects, flammability, toxicity, and cost.

In the early days, people used whatever worked.  All Gen 1 refrigerants were either flammable, toxic, or both.  Examples included: sulfur-dioxide, ammonia, propane, and methyl chloride.  They were used mostly for industrial processes.  Large scale adoption of A/C for cars and homes had not arrived yet.

Gen 2 Refrigerants (1930 to 1990)

In 1928, Charles Kettering and Thomas Midgely at GM’s research labs discovered a better refrigerant – a CFC (carbon/fluorine/chlorine) which they called R12.  R12 was considered the miracle refrigerant (stable, non-toxic and non-flammable) and became widely used for things like refrigerators, auto air-conditioners, window air-conditioners.  R11 (CFC) was soon used in building chillers and R22 (HCFC) in residential and commercial A/C.

 By 1974, scientists were raising the issue of CFCs and their ozone depletion potential (ODP) in the atmosphere.  Further research confirmed this, and by 1987, the Montreal Protocol was adopted.  To comply, the US Congress passed the Clean Air Act Amendments in 1990, which phased out CFCs, HCFCs, and later HFCs, prohibited venting refrigerants, and required certified equipment and licensing to service equipment.  R-134a became the main replacement for R-12 with blends being used to replace other refrigerants.

              ODP concerns faded away as the world turned its’ attention to global warming.  Just as ODP became the death of the CFCs and HCFCs, Global Warming Potential (GWP) became the death of HFCs and associated blended refrigerants.  R600a and R290 both have a GWP of 3, as compared to 1,430 for R-134a.

              While the rest of the world was still using Gen 3 refrigerants, Europe led the way using isobutane (R600A) and propane (R290) in appliances and smaller systems.  Today, more than seven hundred million R600A domestic refrigerators are used worldwide.  The United States has been slower to adapt but is heading down a similar path – with other refrigerants in some applications.  Auto air-conditioners switched to R-1234yf refrigerant beginning in 2015.

In 1997, InSource got our start by building service tools and equipment for the refrigerant recycling and recovery industry, focused on Gen 2 and Gen 3 refrigerants.  Beginning in 2003, InSource began building charged components and sub-systems for OEM refrigeration manufacturers – primarily with Gen 3 refrigerants.  We have extensive experience in building refrigeration systems for our customers using R-134a, R-513 and R-404a.

              InSource has provided hoses and service valves for this Gen 4 refrigerants to OEM suppliers for service and R/R/R equipment.  Some or our refrigeration customers have already changed to R290, and we are assisting others on the changeover for the systems we build for them.  InSource has prototyped such systems and are prepared to build them in support of their plans.

If you want help with your company’s needs to convert to flammable refrigerants, reach out to Fred Manz by sending an email to fred.manz@insource.tech.

[This is the first article of a multi-part series on Refrigeration. Click here to read the next article.]