Propane As a Refrigerant Reduces Global WarmingIn response to the Dec. 3, 2007 article “Old and New Refrigerants Under Scrutiny,” it is sad that federal powers (perhaps under persuasion from some industry lobbyists) have decided to soon ban HCFC-22. R-22 has an ozone depletion rating of 0.05, which is 1/20th the ozone depletion rating of CFC-12 and a Global Warming Potential (GWP) of 1800, which is 1/6 of the GWP (10,900) of R-12.
It is now perfectly clear that the refrigerant manufacturers, in their race to produce non-ozone-depleting refrigerants, completely ignored the global warming properties of their new HFC refrigerants. Now they appear to be locked into these and eager to promote and sell them.
For instance, compared with CO2, which has a GWP of 1.0, HFC-134a has a GWP of 1430, HFC-410A’s [GWP] is 2100, HFC-404A GWP is 3900 and HFC-507’s [GWP] is 4000. I believe these are shockingly high compared with R-290 (propane) whose GWP is -20 (that is, minus 20; in other words, propane reduces global warming compared with the others which all increase it) and R-744 (CO2) whose GWP is 1.0.
Further, while CO2 needs extra-heavy compressors and piping, propane is a near drop-in for R-12 (with some consideration of suction control) and R-22 (with a slight capacity reduction) and works with all mineral lubricants.
While propane is certainly flammable, proposing its use in domestic refrigerators or window conditioners creates a shout of horror by the same people who think nothing of having propane cylinders containing 16 or more ounces on their pantry shelves. For those interested in propane (R-290) as a refrigerant, I have, and will e-mail as a PDF attachment, an article that contains propane line sizes for refrigeration if you contact me at firstname.lastname@example.org.
Dan Kramer, P.E.
Don't Moonlight in Your Daytime FieldI read the article “Why Techs Work ‘Off the Clock’” [Jan. 28] and have to ask these gentleman if they realize they could be creating their own short hours?
As a young man with a family, I, too, ran short and worked off the clock. The key difference is I worked out of my field. I ran service as an ice machine tech and did plumbing on the side - piece work. A friend of mine and I even did air conditioning unit changeouts when our primary source of income was refrigeration service. What we did not do is compete with our employer. Our employers knew what we did and that we did not take the bread and butter from everyone else for ourselves.
I agree with them all that moonlighting can be necessary and is great for toy buying or taking the family somewhere special. But, you do not compete in your field. You do not take the business from your employer and your co-workers, then complain you aren’t getting your hours.
Now I am old and manage a wholesale house. I always remember the tech that wanted to buy five compressors for cash to do jobs his company should have gotten. His company was not and never became my customer, but they did know who saved them five compressor changeouts. But, what the devil, ethics do not count anymore!
United Refrigeration Inc.
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