Bryant 556A - Manual (Page 6)

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.
• R-410A refrigerant cylinders have a dip tube which allows liquid to flow out of cylinder in upright position.
• Recovery cylinder service pressure rating must be 400 psig, DOT 4BA400 or DOT BW400.
• R-410A systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold hose.
• Manifold sets should be 700 psig high side and 180 psig low side with 550 psig low-side retard.
• Use hoses with 700 psig service pressure rating.
• Leak detectors should be designed to detect HFC refrigerant.
• R-410A, as with other HFCs, is only compatible with POE oils.
• Vacuum pumps will not remove moisture from oil.
• Do not use liquid-line filter driers with rated working pressures less than 600 psig.
• Do not install a suction-line filter drier in liquid line.
• POE oils absorb moisture rapidly. Do not expose oil to atmosphere.
• POE oils may cause damage to certain plastics and roofing materials.
• Wrap all filter driers and service valves with wet cloth when brazing.
• A liquid-line filter drier is required on every unit.
• Do not use an R-22 TXV.
• If indoor unit is equipped with an R-22 TXV, it must be changed to an R-410A TXV.
• Never open system to atmosphere while it is under a vacuum.
• When system must be opened for service, break vacuum with dry nitrogen prior to opening to atmosphere.
• Always replace filter drier after opening system for service.
• Do not vent R-410A into the atmosphere.
• Do not use capillary tube coils.
• Observe all warnings, cautions, and bold text.
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