Food for thought on refrigerants, coils and high-efficiency systems.

The 2012 AHR Expo featured no shortage of aluminum “micro-channel” coils in residential equipment. Photo by Jim Wheeler


Last year, at this same time I wrote that experts at the 2011 AHR Expo warned there might be severe refrigerant shortages and price increases due to the lack of a key ingredient, fluorspar from China. Although there have indeed been some drastic price increases, especially when it comes to R22, the shortages simply didn’t happen. Why not? Well, according to one source, everything became available for the right price. Need I say more?

However, as many of you already know, the price of R22 has recently jumped as much as 40%. And the reason for this, according to a spokesman for a major refrigerant manufacturer (who prefers not to be named), is that the U.S. Environmental Protection Agency, “has violated our rights as a manufacturer and the best interests of the public in general by arbitrarily choosing to greatly reduce the amount of R22 that we can manufacture this year.”

Cliplight’s Super Seal with a Nordyne micro-channel evaporator coil. Photo by Jim Wheeler

Aluminum coils

For the past few years I’ve been writing that aluminum “micro-channel” coils are the future of our industry because they are cheaper to manufacture and they provide more cooling capacity per square foot, so condensing units and evaporator coils don’t have to be as large to reach higher efficiencies. And a look around at the residential equipment on the floor at this year’s AHR Expo proved that such coils aren’t the future, they’re the now!

Nordyne, Rheem and Janitrol were some of the few major U.S. HVAC equipment manufacturers at the show, and at least two of them were sporting micro-channel coils. I stopped to take a long look at Nordyne’s new 18-SEER offering, which has an interesting micro-channel evaporator. However, Nordyne explained that micro-channel outdoor coils are not offered on heat pumps yet, because it is still working on a way to remove water in the defrost cycle.

Of course, the problem that most service people have with aluminum coils is that they are almost impossible to repair whenever there’s a leak, so we find a lot of resistance to their acceptance. Yet, Trane has used aluminum in most of its residential condenser coils for many years with few problems. Also, I noted that one company, Cliplight Mfg. (www.cliplight.com), had a Nordyne evaporator on display to show how its Super Seal product can be used to stop refrigerant leaks from the inside (the company damaged the coil to create a leak).

Fujitsu’s new variable-speed 27.2-SEER RLS2 residential split system. Photo courtesy of Fujitsu

In addition to this, may I state that the EPA is creating deliberate future shortages of R22 by failing to enforce its own laws on refrigerant dumping (into the atmosphere), which has resulted in almost no return of R22 from residential HVAC service companies for reclamation. So the viable future for this product remains bleak.

What about “drop-in” replacements? Although a marketing spokesperson for DuPont told me that its ISCEON M99 refrigerant can be used as an R22 replacement on many residential A/C systems and on almost all systems with suction accumulators when an extra 25% POE lubricant charge is added, the folks at Copeland (a compressor manufacturer) said that simply isn’t advisable.

LG showed off its Multi V III condensing units for commercial use. Photo by Jim Wheeler

Higher efficiencies

As I’m sure you already know, the minimum operating efficiency for most U.S. residential air conditioners is 13-SEER, but the efficiencies at the top of the lines continue to rise. I believe a couple years ago Nordyne introduced the highest-efficiency (23-SEER) residential A/C system, which uses variable speeds and a rotary compressor. I remember that someone from another compressor manufacturing company whom I spoke to at the time about the use of a rotary (which is uncommon on larger residential split systems), saying that particular type of compressor wouldn’t last and would quickly burn itself out. So I asked a Nordyne spokesperson about this at the show, and he claimed that it has only seen three compressor failures to date…interesting.

Speaking of higher efficiencies, Fujitsu was at AHR showing off its new variable-speed 27.2-SEER RLS2 residential split system. Climatemaster was there with its new Tranquility 22 fully digital geothermal heat pump, which is rated as high as 22-EER. Korean manufacturer LG proudly displayed its Multi V III commercial condensing units, which claim a 21.8-IEER (special rating for variable-speed units) efficiency.

I’ll have more AHR observations next month.

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