user manual

14
XVI. R-410A REFRIGERANT
A. TOOLS REQUIRED FOR INSTALLING & SERVICING R-410A MODELS
M
anifold Sets:
-Up to 800 PSIG High Side
-Up to 250 PSIG Low Side
-550 PSIG Low Side Retard
Manifold Hoses:
-Service Pressure Rating of 800 PSIG
Recovery Cylinders:
-
400 PSIG Pressure Rating
-Dept. of Transportation 4BA400 or 4BW400
B. SPECIFICATION OF R-410A:
Application: R-410A is not a drop-in replacement for R-22; equipment designs must
accommodate its higher pressures It cannot be retrofitted into R-22 condensing units.
Physical Properties: R-410A has an atmospheric boiling point of -62.9°F and its satu-
ration pressure at 77°F is 224.5 psig.
Composition: R-410A is an azeotropic mixture of 50% by weight difluoromethane
(HFC-32) and 50% by weight pentafluoroethane (HFC-125).
Pressure:
The pressure of R-410A is approximately 60% (1.6 times) greater than R-22.
Recovery and recycle equipment, pumps, hoses and the like need to have design pres-
sure ratings appropriate for R-410A. Manifold sets need to range up to 800 psig high-
side and 250 psig low-side with a 550 psig low-side retard. Hoses need to have a ser-
vice pressure rating of 800 psig. Recovery cylinders need to have a 400 psig service
pressure rating. DOT 4BA400 or DOT 4BW400.
Combustibility: At pressures above 1 atmosphere, mixture of R-410A and air can
become combustible. R-410A and air should never be mixed in tanks or supply
lines, or be allowed to accumulate in storage tanks. Leak checking should never
be done with a mixture of R-410A and air. Leak checking can be performed safely
with nitrogen or a mixture of R-410A and nitrogen.
C. QUICK REFERENCE GUIDE FOR R-410A
• R-410A refrigerant operates at approximately 60% higher pressure (1.6 times) than
R-22. Ensure that servicing equipment is designed to operate with R-410A.
• R-410A refrigerant cylinders are pink in color.
• R-410A, as with other HFC’s, is only compatible with POE oils.
• Vacuum pumps will not remove moisture from oil.
• R-410A systems are to be charged with liquid refrigerants. Prior to March 1999,
R-410A refrigerant cylinders had a dip tube. These cylinders should be kept upright for
equipment charging. Post March 1999 cylinders do not have a dip tube and should be
inverted to ensure liquid charging of the equipment.
• Do not install a suction line filter drier in the liquid line.
• A liquid line filter drier is standard with every unit. Only manufacturer approved liquid
line filter driers can be used. These filter driers are rated for minimum working pres-
sure of 600 psig.
• Desiccant (drying agent) must be compatible for POE oils and R-410A.
!
CAUTION
R-410A systems operate at higher pressures than R-22 systems. Do not use
R-22 service equipment or components on R-410A equipment.