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3.0 INSTALLATION
3.1 TOOLS & REFRIGERANT
3.1.1 TOOLS REQUIRED FOR INSTALLING AND SERVICING R-410A MODELS
Manifold 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 BW400
3.1.2 SPECIFICATIONS 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 heat pumps.
Physical Properties: R-410A has an atmospheric boiling point of -62.9°F [-52.7°C] and
its saturation pressure at 77°F [25°C] is 224.5 psig.
Composition: R-410A is a near-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 must have design
pressure 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
service pressure rating of 800 psig. Recovery cylinders need to have a 400 psig service
pressure rating, DOT 4BA400 or DOT BW400.
Combustibility: At pressures above 1 atmosphere, a 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.
3.1.3 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 light rose in color.
• R-410A, as with other HFCs, is only compatible with POE oils.
• Vacuum pumps will not remove moisture from POE oil used in R-410A systems.
• 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 factory-approved outdoor liquid line filter drier is shipped with every unit and must
be installed in the liquid line at the time of installation. If only the air-handler is being
replaced on an existing system, the existing filter drier must be replaced at the time of
installation with a field supplied filter drier. IMPORTANT: A bi-flow filter drier must be
used for heat pump applications. Filter driers must be rated for minimum working
pressure of 600 psig. The filter drier will only have adequate moisture-holding capaci-
ty if the system is properly evacuated.
• Desiccant (drying agent) must be compatible for POE oils and R-410A refrigerant.
Ambient and Tube
Thermometers
M
anifold
G
auge
S
et
B
razing
R
ods
T
orch Nitrogen
R
eclaimer
Recovery
Cylinders
A
llen Wrench
C
rescent Wrench
!
NOTICE
R-410A systems operate
at higher pressures
than R-22 systems. Do
not use R-22 service
equipment or compo-
nents on R-410A equip-
ment.
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