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AIR CONDITIONER WITH R--410A QUICK REFERENCE GUIDE
R--410A refrigerant operates at 50--70 percent higher pressures than R--22. Be sure that servicing equipment and replacement components
are designed to operate with R--410A. R--410A refrigerant cylinders are rose colored.
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R--410A refrigerant cylinders manufactured prior to March 1, 1999, have a dip tube that allows liquid to flow out of cylinder in upright
position.
Cylinders manufactured March 1, 1999 and later DO NOT have a dip tube and MUST be positioned upside down to allow liquid to flow.
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Recovery cylinder service pressure rating must be 400 psig. DOT 4BA400 or DOT BW400.
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R--410A systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold hose.
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Manifold sets should be minimum 700 psig high--side and 180 psig low--side with 550 psig low--side retard.
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Use hoses with minimum 700 psig service pressure rating.
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Leak detectors should be designed to detect HFC refrigerant.
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R--410A, as with other HFCs, is only compatible with POE/PVE oils.
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Vacuum pumps will not remove moisture from oil.
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Only use factory specified liquid--line filter driers with rated working pressures no less than 600 psig.
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Do not install a suction--line filter drier in liquid line.
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POE/PVE oils absorb moisture rapidly. Do not expose oil to atmosphere.
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POE/PVE oils may cause damage to certain plastics and roofing materials.
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Wrap all filter driers and service valves with wet cloth when brazing.
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A R--410A liquid--line filter drier is required on every unit.
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Do not use an R--22 TXV.
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Never open system to atmosphere while it is under a vacuum.
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When system must be opened for service, break vacuum with dry nitrogen and replace filter driers.
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Always replace filter drier after opening system for service.
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Do not vent R--410A into the atmosphere.
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Observe all warnings, cautions, and bold text.
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Do not leave R--410A suction line driers in place for more than 72 hrs.
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