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ATTENTION INSTALLERS AND SERVICE TECHNICIANS!
R-410A Refrigerant Quick Reference Guide
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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 refrigerant.
•
R-410A refrigerant cylinders are rose colored.
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Recovery cylinder service pressure rating must be 400 psig, DOT 4BA400 or DOT BW400.
•
R-410A refrigerant systems should be charged with liquid refrigerant. Use a commercial type metering
device in the manifold hose when charging into suction line with compressor operating.
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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.
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Leak detectors should be designed to detect HFC refrigerant.
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R-410A refrigerant, as with other HFCs, is only compatible with POE oils.
•
Vacuum pumps will not remove moisture from oil.
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Do not use liquid-line filter driers with rated working pressures less than 600 psig.
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Do not leave R-410A refrigerant suction line filter driers in line longer than 72 hours.
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Do not install a suction-line filter drier in liquid-line.
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POE oils absorb moisture rapidly. Do not expose oil to atmosphere.
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POE 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 factory-approved liquid-line filter drier is required on every unit.
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Do NOT use an R-22 expansion device.
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If indoor unit is equipped with an R-22 expansion device, it must be changed to a hard-shutoff R-410A
refrigerant expansion device.
•
Never open system to atmosphere while it is under a vacuum.
•
When system must be opened for service, recover refrigerant, evacuate then break vacuum with dry
nitrogen and replace filter driers. Evacuate to 500 microns prior to recharging.
•
All indoor coils must be installed with a hard-shutoff R-410A refrigerant expansion metering device.
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Do not vent R-410A refrigerant into the atmosphere.
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Do not use capillary tube coils.
•
Observe all
warnings
,
cautions
, and
bold
text.
Page 38
Summary of Contents for 38AUM Series
Page 31: ...TYPICAL WIRING SCHEMATIC 38AUMZ07 08 Page 31...
Page 32: ...TYPICAL WIRING SCHEMATIC 38AUMD12 14 Page 32...
Page 33: ...TYPICAL WIRING SCHEMATIC 38AUMD16 Page 33...
Page 34: ...CHARGING CHARTS Page 34...
Page 36: ...CHARGING CHARTS cont Page 36...
Page 37: ...CHARGING CHARTS cont Page 37...
Page 41: ...NOTES Page 41...
Page 42: ...NOTES Page 42...
Page 43: ...NOTES Page 43...