Conservation + Comfort: Everything You Wanted To Know About Refrigerants (But Were Afraid To Ask)
November 10, 2008
In the holiday movie classic, “A Christmas Story,” nine-year-old Ralphie wants an official Red Ryder carbine-action 200-shot range model air rifle, but he’s told by his mother, teacher, and even Santa Claus that the BB gun is too dangerous and “you’ll shoot your eye out.” Unfortunately, there are many in the HVAC industry who have the same fear about working with R-410A. They believe that the high-pressure refrigerant could blow up if left in a warm truck or possibly cause an air conditioning system to explode while charging. If either of these situations has occurred, there hasn’t been much media attention about it.
What is more probable is that these unlikely scenarios may have been discussed during R-410A training sessions and have now moved into the world of “contractor lore.”
Even if most contractors don’t buy into these myths, many still have lingering concerns about the phaseout of R-22 and the adoption of R-410A. That’s why we asked experts from ICP, Arkema, Emerson, and ICOR to address some of the most common concerns about R-410A and the phaseout of R-22.
ICP ADDRESSES THE ISSUESInternational Comfort Products (ICP) LLC, is a North American manufacturer of heating and cooling equipment whose major brands include Heil®, Tempstar®, Comfortmaker®, Arcoaire®, KeepRite® and Day & Night™. ICP technical trainer, Mark Gallier, answers the common questions he gets regarding R-410A:
Can R-410A be used (retrofitted) in an R-22 system?
No. The components of an R-22 system are not designed for the higher pressures of R-410A, and the mineral oil used with R-22 is not compatible with R-410A.
Can existing line sets be used when replacing R-22 equipment with R-410A equipment?
When replacing older equipment, the best approach is to replace the line set. If it cannot be replaced, the line set can be used if it is cleaned and sized properly. In addition, low areas or traps in existing line sets should be cut and drained of any residual oil.
Can an R-410A outdoor unit be used with an existing R-22 indoor coil?
The answer to this question will vary from manufacturer to manufacturer. In some cases, the coil was designed for both refrigerants.
In this case, you can change the metering device and use the coil with a properly matched outdoor unit. It is important to verify this with the manufacturer.
Will I need different recovery equipment to use with R-410A?
Some recovery machines are compatible with HCFC (R-22) and HFC (R-410A) refrigerants. Check the data plate on the machine or contact the manufacturer with the model number to find out the refrigerant compatibility. Also make sure that the recovery cylinder is a 400-psi (DOT BW400) cylinder when you are working with R-410A.
ARKEMA ANSWERS THE QUESTIONSArkema is the world’s second largest producer of fluorochemicals and manufactures refrigerants sold under the Forane trademark. Craig Thomas, marketing manager-refrigerants, Arkema, answers questions regarding the phaseout of R-22:
What is the outlook for supply and demand of R-22?
Up until 2010, we believe that the supply of HCFC-22 (R-22) will be similar to its current state. The supply of R-22 after 2010 is less certain. In September 2007, the federal government agreed to reduce the cap on HCFC consumption in the United States by another 10 percent, leaving only 25 percent of the original HCFC cap. Demand for R-22 is still strong in the United States, and the service market remains a consistent source of demand for refrigerants. The overall concern is that the total demand for R-22 is forecasted to be the same as the cap on R-22.
What refrigerants are currently available to take the place of R-22?
The market currently has several R-22 alternatives available for new OEM use and retrofit applications. Among residential air conditioning manufacturers, most have selected R-410A. R-410A, along with R-134a, is also used in commercial air conditioning. For refrigeration, R-404A and R-507A are the leading OEM choices, with most new units designed to use either refrigerant. For retrofits, there are several possibilities that can work with current R-22 equipment; however, they all require different accommodations when retrofitting older R-22 systems. For R-22 retrofits, R-427A (an HFC) has been found to be an acceptable candidate, matching the properties of R-22 with no ozone depletion and a low GWP [global warming potential].
Can you service existing R-22 units after 2010 using virgin R-22?
Yes. Under the regulations today, certified contractors will be allowed to service existing R-22 units with R-22. After 2010, there will not be a ban on service for R-22 equipment manufactured before December 31, 2009.
EMERSON OFFERS EXPLANATIONSEmerson Climate Technologies, a business of Emerson, is a leading provider of HVACR solutions for residential, industrial, and commercial applications. Emerson Climate Technologies’ innovative solutions include industry-leading brands such as Copeland Scroll® and White-Rodgers. Karl Zellmer, vice president of sales at Emerson Climate Technologies, answers the following questions:
Do the higher pressures of R-410A cause more compressor failures?
R-410A operates at 50 to 70 percent higher pressures, and the system safety controls must be compatible. All R-410A units use a compressor that is specially designed for the higher suction and discharge pressures of R-410A. The compressor operates at the differential pressure of the refrigerant that is pumping, that is, absolute discharge pressure/absolute suction pressure. In many cases, the pressure ratio that a compressor operates at is lower with R-410A than it is at the same evaporating/condensing temperature combination with R-22.
We are not seeing an increased frequency in Copeland Scroll compressor failures nor shorter life spans as a result of the higher pressure. Air conditioning units using R-410A have been thoroughly tested by OEMs and independent laboratories. The millions of installations already up and running around the world support that R-410A systems meet today’s demanding reliability standards. In fact, many manufacturers currently observe lower failure rates with R-410A systems using Copeland Scroll compressors than with R-22 systems.
Are there different installation practices for R-410A equipment?
Upon installing or servicing a unit with polyolester (POE) oil, make sure that a new R-410A-compatible filter drier is installed anytime the system is opened. Vacuum alone will not remove moisture. Brazed-in or “sweat”-style filter driers must be cut out of the system to avoid contamination.
What are the alternatives for replacing R-22?
Replacing old R-22 systems with new R-410A units can help protect customers against potentially higher costs for servicing and maintaining R-22 units. Installing a new R-410A unit means being able to consider the full life of the equipment, without concern over future availability of R-22 and necessary service components. This is particularly true with commercial applications where the common need for multiple HVAC systems makes the total cost a critical part of the buying decision.
When considering a retrofit with a replacement refrigerant, oil return to the compressor is critical to compressor reliability and the overall long-term reliability of the system.
The HFC refrigerant R-410A has been tested by Emerson and is our recommended choice for a non-ozone depleting (HFC) refrigerant to replace R-22 in new equipment. However, if you do service an R-22 system with an HFC retrofit refrigerant, R-407C with POE oil is acceptable for compressor reliability and warranty.
ICOR DISCUSSES OPTIONSAccording to Gordon McKinney, vice president and COO, ICOR International, various options are available to the industry in regard to dealing with the future shortage of R-22. “Government officials, along with many industry experts, believe there will be significant challenges for the R-22 supply chain in the very near future. Estimates are that the gap between what is being allocated by the government for R-22 production and importation falls short of what the service industry’s requirements will be by as much as 40 million pounds per year,” said McKinney.
“There are four basic ways users can close the gap: replace the equipment; recover, recycle, or reclaim old refrigerant; reduce system leaks; or convert existing R-22 systems to an alternative HFC refrigerant.”
Commented McKinney, “Companies trying to convince consumers that replacing their equipment is the only practical option are poorly informed about the performance success of R-22 direct replacements like NU-22B® (R-422B) or they are being shortsighted to the looming economic crisis. Historically, the new equipment business always suffers during an economic downturn.”
“Service-related products like NU-22B are rapidly growing in acceptance as they provide a safe, easy-to-use, efficient, and price-practical solution to the R-22 crisis and the economic crisis,” said McKinney.
Publication date: 11/10/2008