Thursday, December 13, 2012

Beyond or Beside HFCs

The Air Conditioning, Heating & Refrigeration NEWS VOL.247 NO.14

By Peter Powell

December 3, 2012
My column in the Nov. 12 issue of The NEWS focused on HFCs, especially low GWP HFCs as retrofits for R-22 systems. This column will focus on what I used to call “beyond HFC” refrigerants, although these days, the term might be “other than HFC” refrigerants.
Let’s look at the refrigerant options now available or soon to come and then how they factor into the HFC picture.

Refrigerant Options
First, consider ammonia beyond its industrial applications. It appears to be entering the commercial sector. Trade associations like the International Institute of Ammonia Refrigeration have long advocated its value in commercial. That was noted in papers at IIAR’s conference this past spring. And a report from the U.S. Environmental Protection Agency’s (EPA) GreenChill Advanced Refrigeration Partnership announced that a supermarket with ammonia as part of its refrigeration system would be coming on line in the near future.
The next — and by far the highest profile for several years — non-f-gas refrigerant has been CO2. No other refrigerant has generated as many case histories and glowing testimonies coming into my email box. And this past year, The NEWS has reported extensively about the technology in both cascade and transcritical applications. It is that latter approach that is causing wider use of CO2. At the same time, it is a refrigerant not all that familiar to those who typically work with HCFCs and HFCs. In fact, it is not a manufactured refrigerant; it is naturally occurring. How it is captured, packaged, and distributed for use in mechanical refrigeration systems has typically taken place outside the HVACR wholesaling network. And there is a learning curve for technicians, and there may be certain zoning and code issues depending on where it might be used.
HCs got a boost in 2012 with EPA SNAP approval for some HCs in some applications. It didn’t open a floodgate of places to use it, but it is a start. Part of the acceptance relates, again, to codes and zoning laws as well as liabilities and available equipment. One recurring theme I heard from contractors is that they would be willing to work with HCs — if equipment and warranties are in place and if it is allowed by municipalities.
HFOs are refrigerants being developed by several refrigerant manufacturers who traditionally have developed CFCs, HCFCs, and HFCs. One HFO — 1234yf — got a bit of pushback in 2012 when one automotive manufacturer balked at using it in auto a/c in place of HFC-134a, which was supposed to be facing phaseout in automotive in Europe. The question raised by the end users over safety of the yf was countered by the refrigerant manufacturers who said there was not a safety issue.
That same safety issue does not appear to be a factor on the stationary side since automotive and stationary systems are so different. HFOs do carry an A2L safety rating (which means slightly flammable) although advocates say it would take some doing to create a spark that could cause a problem. Work continues on a wide variety of HFOs in stationary applications and they have remained refrigerants high on the radar screen at the biennial HVACR-related conferences at Purdue University. They were discussed in 2010 and even more so in 2012.

Refrigerant Variety
CO2, HCs, HFOs, and ammonia seem to be gaining more and more attention in commercial refrigeration in North America. They seem to be doing so regardless of the future of HFCs. Whether growth is due to fears of possible phasedowns in HFC production or just because they are proving to be viable ways to create refrigeration is unclear.
But what is clear to refrigeration contractors is that CO2, HCs, HFOs and ammonia merit attention. If an installing contractor is no longer around and end users call you to work on their systems, it would be best to ask a lot about the system — including the refrigerant. How much you know about a wide variety of refrigerants may be a factor in getting more jobs in the future.

Publication date: 12/3/2012
Peter Powell is Refrigeration Editor. E-mail him at

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.