r-410a refrigerant certification course design air university 2016

R-410A Refrigerant Certification Course

DESIGN AIR UNIVERSITY2016

DESIGN AIR UNIVERSITY 2

Topics• Links to info. sites

• History & Names

• HFC phase-out

• Properties of R-410A

• Chemistry

• Temp./ Pressure chart

• Safety

• Rules & Regulations

• Oils

• Tools

• Charging

• Recommendations


About website links

Some slides contain links to websites where you can access added information. These links are in light blue text. Depending on the speed of your internet connection, you may have to wait for the linked sites to load and appear on screen.

After visiting a site, just close the window while leaving your browser open. This will return you to this training program. If you aren’t interested, just don’t click the links.

If you don’t have a high-speed internet connection, you have probably already learned patience.


Who invented R-410A?

• AlliedSignal was an aerospace, automotive and engineering company that acquired and merged with Honeywell for $15 billion in 1999, after which the new group adopted the Honeywell name.


Allied Signal

• Products include Fram filters, Autolite spark plugs and Prestone anti-freeze.

• Genetron refrigerants.


Names, lots of names

• Genetron AZ-20 is Honeywell's original name for R-410A, a Honeywell invention that entered the scene in a test market in 1993 as a chlorine-free R-22 replacement. With its energy efficiency and none-ozone depletion advantages over R-22, R-410A is now the leading replacement for R-22 in new residential air conditioners.


Other Names• Carrier calls it Puron

• Dupont calls it Suva 9100

• Rheem calls it ProZone

• Lennox calls it Environ

• Panasonic calls it Cooleron


It’s all the same stuff . . . R-410A

• In fact, if you buy a jug of “Puron”, it will probably have Allied Signal’s or Honeywell’s name on it.


Bye-bye R-22!

• R-22 has disappeared from the new equipment marketplace since 2010.

• R-410A is the refrigerant of choice to replace R-22.


Some advertisers may be guilty of exaggeration.

• For an impartial, third party discussion of the phase-out of HCFCs like R-22, you and your customers can go to the website of the U.S. Environmental Protection Agency (EPA) at:

R-22 phase-out discussion at EPA website

http://www.epa.gov/ozone/title6/phaseout/22phaseout.html


Why is R-410A so desirable?

• Operates in the same temperature ranges as R-22.

• The cooling equipment can share the same basic design as traditional equipment.

• For example . . .


41° F.

113° F.

70 235

R-22

122 380

R-410A


R-410A

• Cylinder color: rose (pink).

• R-22 comes in a green cylinder.

• Never mix these refrigerants together.


Characteristics of R-410A

• Operates at pressures about 60% higher than R-22.

• Used with POE oil.

• For new, specially-designed equipment only.

• Cannot be retrofitted into older equipment !!!


Other characteristics• A 500 micron vacuum will NOT remove

all moisture from the system.

• The POE oil grabs onto water and won’t give it up to our vacuum pumps.

• Always install a filter drier on the liquid line whenever the system has been open to the atmosphere; even new systems!


Replacing Driers

• Always cut out the old drier.

• Never use your torch for removal.

• The heat will drive the captured moisture out of the drier back into the system.


Basic chemistry

• CFC = chlorofluorocarbon (ie: R-12).

• HCFC = hydrochlorofluorocarbon (R-22).

• HFC = hydrofluorocarbon (R-410A).


CFCs

• Comprised of chlorine, fluorine & carbon.

• Extremely stable and long-lived.

• Drift into the highest levels of the troposphere where they will destroy many ozone molecules for many years.

• Phased out of production in 1996.


HCFCs• Comprised of hydrogen,chlorine, fluorine

& carbon.

• Less stable and long-lived.

• Break down quickly in the lower levels of the atmosphere.

• Only 2% to 5% of the ozone depletion potential of CFCs.


HFCs

• Comprised of hydrogen, fluorine & carbon.

• No chlorine atom.

• Zero ozone depletion potential.


Some new terms:

• When two blended refrigerants separate easily, they are called Zeotropic.

• When blended refrigerants don’t segregate in the system, but form a stable chemical composition they are called Azeotropic.


R-410A Chemistry

• 50 - 50% blend of HFC-32 and HFC-125.• Near-azeotropic properties.• Chemical name:

– Difluoromethane, Pentafluoroethane


Concerns with Blends

• Fractionation

• Temperature glide


Fractionation• The tendency of one or more

components of a blend to leak at a faster rate than other components.

• Changes the composition of the remaining blend still in system.

• Loss of performance results.

• Occurs in zeotropic blends like R-407C.


What is Temperature Glide?

• Difference in two temperatures at a given constant pressure.

• For example . . .


In the evaporator . . .

• The temperature at which liquid refrigerant first begins to boil is known as the saturated liquid temperature, (also known as the bubble point temperature).


2nd Temperature

• The temperature at which the last drop of liquid refrigerant has boiled off is known as the saturated vapor temperature, (also known as the dew point temperature).


Temperature Glide

• At a constant pressure, the difference between the saturated vapor temperature and the saturated liquid temperature is referred to as the temperature glide of the refrigerant.

• The temperature glide of a single compound refrigerant like R-22 is zero.


R-410A Temperature Glide

• The temperature glide of R-410A is 0.2°F or essentially zero as well.

• This is good!


Key Attribute of R-410A

• Near-Azeotropic properties means it acts like a single compound with minimal temperature glide or fractionation potential.


Benefit to you is . . .

• A temperature-pressure chart can easily be used for charging, refrigerant cycle analysis and diagnosis.

• Advance to the temperature pressure chart for R-410A


Temp. °F Press.

26.3° 90

28.9° 95

31.4° 100

33.8° 105

36.2° 110

38.5° 115

40.7° 120

42.8° 125

44.9° 130

47° 135

49° 140

50.9° 145

52.8° 150

Temp. °F Press.

54.7° 155

56.5° 160

58.3° 165

60° 170

61.7° 175

63.4° 180

65° 185

66.6° 190

68.2° 195

69.8° 200

71.3° 205

72.8° 210

74.2° 215

Temp. °F Press.

75.7° 220

77.1° 225

78.5° 230

79.9° 235

81.3° 240

82.6° 245

83.9° 250

86.5° 260

89° 270

91.5° 280

93.9° 290

96.3° 300

98.5° 310

Temp. °F Press.

100.7° 320

105° 340

109.1° 360

113.1° 380

116.9° 400

120.5° 420

124.1° 440

127.5° 460

130.8° 480

134° 500

137.2° 520

140.2° 540

143.2° 560


Tech Tip

• You never want to see a suction pressure below 100 psi with R-410A air conditioning systems.

• Why?

• Look it up on the previous slide.

• At 100 psi, the evaporator will begin to frost over.


Refrigerant Comparison

• Refrigerant R-12 R-22 R-410A

• ODP* 1 0.055 0

• GWP° 8500 1700 1975

• Type CFC HCFC HFC

• Developed 1931 1936 1991– * ODP = ozone depletion potential

– ° GWP = global warming potential. Source: IPCC Climate Change 2001


Automotive Refrigerants

• Refrigerant R-134A R-744 (CO2)

• ODP* 0 0

• GWP° 1300 1

• Type HFC natural element

• Developed 1990s 1850s– * ODP = ozone depletion potential

– ° GWP = global warming potential.


Is R-410A a “Perfect Refrigerant”?

• No. There is no “perfect refrigerant.”

• It has a slightly higher Global Warming Potential than R-22.

• However, this is somewhat offset because R-410A has a 5 - 6% higher Energy Efficiency Rating than R-22.


Don’t vent R-410A !

• R-410A is covered by the same rules of the Clean Air Act as all other refrigerants.

• Just because it doesn’t deplete the ozone layer, doesn’t mean you can release it.


Safety

• Most of the safety precautions are the same for R-410A as R-22.

• For example, never expose cylinders of either refrigerant to temperatures above 125° F.

• Use the same storage rules for both.


Safety

• R-410A has been confirmed to be in the low toxicity range.

• ASHRAE Safety Group: A1/A1.

• UL Class: Practically Non-flammable.

• DOT Green Label: Non-flammable.


Safety

• Ingestion:

– Don’t drink it!

– Don’t induce vomiting if someone else does.

– Seek immediate medical attention.


Safety

• Skin or Eye Contact:

– Same as other refrigerants; causes frostbite.

– Flush with lukewarm water.

– Seek immediate medical attention.


Safety

• Avoid exposing it to high temperatures.

– Watch your torch!

– Exposure to flame can produce toxic compounds.

– Contact with red hot metals like abraded aluminum can result in exothermic or explosive reactions.


Safety• Inhalation:

– Same as other refrigerants.

– Attacks central nervous system.

– Causes dizziness & then unconsciousness.

– Slurred speech; loss of muscle coordination.

– Can cause cardiac irregularities & ultimately, death.

– Get to fresh air & seek immediate medical attention.


Safety

• R-410A is heavier than air.

• It will displace oxygen.

• If a leak has occurred in a confined area, ventilate with fresh air before entering.


Oils

• R-22 uses alkylbenzene oil.

• R-410A uses polyol ester (POE) oil.

• Oils must be miscible with refrigerant.– miscible = able to mix together.

• Oils must be matched with the proper refrigerant.


Advantages of POE Oil

• Better oil return properties.

• Better heat transfer characteristics.

• Better lubrication ability.

• Wax free.


Oil Characteristics

• Great lubricant.

– But !

• It’s “hygroscopic”: strong attraction to moisture.

• Will absorb water vapor right into the oil.


Oil Handling Procedures

• Keep POE oil sealed in metal containers.

• Keep condensing unit and compressors sealed until right before brazing.

• Always install a liquid line drier whenever R-410A systems have been exposed to the atmosphere.


POE Oil Warning!

• POE oil is manufactured by combining alcohol and acid which then gives off water. The water is then removed.

• Allowing moisture to enter the system can reverse this process and turn the POE oil to a combination of acid and organic salts!


Oil Disposal

• It’s against the law to just dump waste oil.

• EPA does not classify refrigeration oils as hazardous waste, but . . .

• Do not mix oils with other wastes.

• Do not mix refrigeration oils with waste oils from other sources.


Oil Disposal

• Waste oil is your responsibility.

• Legally you own it . . . for life!

• Recycle it.


POE Oil Safety

• POE oil irritates the skin.

• Wash affected skin with soap & water.

• POE oil has been known to damage some rubber roofs!


Leak repair regulations

• EPA 608 requires technicians to find & repair leaks that are over 15% of the total system charge annually.

• R-410A is covered by this rule as well.


Leak Testing

• Electronic leak detectors designed for HFCs work well.

• So do mixtures of dry nitrogen & R-410A.

• “Bubbles” and Ultrasonic leak detectors can also be used.


Leak Testing Caution!

• Do not use halide leak detectors designed for R-22.

• Never use a mixture of compressed air and R-410A to check for leaks as this mixture is flammable above one atmosphere (ie: 14.7 psi.).


A Word About Driers• Driers must be rated for R-410A.

• Most new driers can be used for all refrigerants.

• Pressure rating of drier’s shell must be higher.


Replacing old R-22 Systems

• The condensing unit and evaporator coil must be replaced with new matched components engineered for the higher pressures of R-410A.

• Expansion valves (TXVs) must be specific to R-410A.


Reusing existing line sets?

• Properly-sized, copper line sets in good condition w brazed connections can be reused with new R-410A equipment.

• They should be cleaned to remove all traces of the old mineral oil.

• Here is one possible flushing agent:Rx11 FlushClick here to research

http://www.nucalgon.com/products/refrig_systemFlushing_rx11flush.htm


Special Tools


Recovery Units

• Must be rated for R-410A.

• Oil-less design is best.


Gauges & Hoses

• High side range to 800 psi.• Low side range to 250 psi. with a 550

psi retard.

• Hoses must be rated to 800 psi.• Do NOT mix refrigerants in your tools.

– Dissimilar oils will become contaminated.


Recovery Cylinders

• Rated for 400 psi.– NOT 300 psi like standard cylinders.

• Color: Gray with yellow top.

• DOT 4BA400 or 4BW400

• Do NOT recover different refrigerants into the same cylinders!


Recovery Cylinders

• Must be replaced or tested (w date stamp) every 5 years.

• Do not mix refrigerants in the same recovery tank!

• Never fill above 80% full.


Charging R-410A Systems

• Most new equipment will employ thermostatic expansion valves (TXVs) to meter refrigerant into the evaporator.

• This is a highly desirable feature which allows improved comfort control by maintaining a fully active evaporator under a wide array of operating conditions.


Charging Procedure

• Charge as a liquid

– Invert cylinder


When charging with liquid . . .

• Use a charging valve

– Such as Ritchie # 41123

– This will flash the refrigerant to the vapor state so that it can safely be put into the suction line of the system.

– 5/16” for most mini-splits.


Charging by Sub-cooling

• Charging is often done by sub-cooling.

• You may already be familiar with this method if the R-22 systems you were installing had TXVs.

• We’ll review it now:



1. Operate the system to stabilize temperatures & pressures.

2. If the outdoor temperature is less than 65°F., restrict the air flow across the condenser until the high side pressure on your red gauge reaches 350 psig.

3. If over 65°F., simply measure the liquid line pressure.



4. Determine the saturation temperature that corresponds to that pressure. You can read this off your red gauge or use a chart for R410A.

5. Measure the liquid line temperature at the service valve on the condensing unit using a fast-acting digital thermometer clamped to the liquid line and insulated from ambient temperatures.



6. Subtract the liquid line temperature from the saturation temperature to get the sub-cooling.


Adjusting the Charge

• If sub-cooling is too low, add refrigerant.

• If sub-cooling is too high, recover refrigerant.

• If the equipment manufacturer does not state a target sub-cooling, use 10°-15°F.


Of course . . .

• Airflow must be correct;

• Refrigerant line sizing must be correct;

• Let the system run for 10-15 minutes to stabilize temperatures & pressures.


Charging by weight

• The preferred method.

• Use the manufacturer’s data to determine how many ounces of refrigerant to add or recover.

• Based on factory charge plus length and diameter of liquid line.


More charging tips: Sight Glass

• Most systems will not have a sight glass.

• Do NOT try to clear the sight glass when charging. You risk an overcharge.

• It is normal for part of the blend to flash to a vapor in the sight glass.

• This will reform into 100% liquid later.


Fast Facts

• R-410A can only be used in equipment designed specifically for it.

• R-410A operates at pressures 60% higher than R-22.


Fast Facts 2

• The saturation temperatures of R-410A are similar to those of R-22.

• Technicians need special tools to work on R-410A systems.

• R-410A comes in pink cylinders.


Fast Facts 3

• R-410A was invented by Allied Signal (now called Honeywell).

• R-410A is non-flammable.

• Do not expose cylinders of R-410A to temperatures above 125° F.*

* The same is true of cylinders of R-22.


Fast Facts 4

• R-410A uses POE oil which is highly hygroscopic (attracts water).

• Always evacuate systems to 500 microns.

• All R-410A systems must have a drier installed in the liquid line.


Fast Facts 5

• Cylinders of R-410A must be inverted when adding refrigerant to a system.

• R-410A must leave the cylinder as a liquid with a charging valve used to flash the liquid to a vapor before being added to a system.


Fast Facts 6

• R-410A does not deplete the ozone layer, but it can never be vented to the atmosphere.

• It must be treated like all other refrigerants covered by the Clean Air Act.

• It is not classified as Hazardous Waste.


Fast Facts 7

• Recovery cylinders are gray with yellow tops.

• Recovery cylinders should only be filled to 80% of their capacity by weight.


Fast Facts 8

• The old line set can be reused when replacing R-22 systems with R-410A equipment.

• Clean the old line set to remove all traces of mineral oil.

• Refrigerants & oils should not be cross-mixed.


In Conclusion

• DESIGN AIR has been selling air conditioning equipment using R-410A for many years.

• These are highly-reliable, efficient and “Green” systems.

• Consumers find them highly-desirable.

r-410a refrigerant certification course design air university 2016

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