Carrier Comfort 50VL D Series Installation Instructions Manual page 34

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