15
7.
Branch pipe connections may be brazed. It is
necessary to purge the pipes with nitrogen during
brazing to avoid oxidation which may block the
refrigerant piping strainers.
8. After refrigerant piping has been installed and
checked for leaks, apply insulation over all flared
connections. See Figure 21.
Outside
Diameter
Recommended
Torque
No torque wrench
available
Finger tighten and
use an appropriately
sized wrench to turn
an additional:
Inches
3/8”
26 ft.-lb. (35 N-m)
1/2 turn
3/4”
60 ft.-lb. (81 N-m)
1 turn
Table 2. Flare Nut Torque Recommendations
Figure 21. Insulate Flared Connections
UNIT
BASE
INSULATE ALL FLARED CONNECTIONS
TO PREVENT CONDENSATION
A
B
CANT ON THE OUTSIDE OF
THE FLARE
MALE FLARE
CONNECTION
Figure 19. Making Connections
(Male to Female Connection)
Figure 20. Tighten Flare Nut
5.
Align the threaded connections with the flared
refrigerant lines. Tighten the flare nuts lightly at
first to obtain a smooth match (Figure 19-B).
6. Once snug, continue another half-turn on each
nut which should create a leak-free joint. A torque
wrench may be used to tighten flare nuts using
table 2 recommendations. See Figure 20.
Do not
over-tighten a flared joint. Flared connections
should always be accessible and must be
insulated to prevent condensation.
IMPORTANT
The compressor in this unit contains PVE
oil (Polyvinylether). PVE oil is formulated for
hydrofluorocarbon (HFC) refrigerants, such as R-
410a, which this system contains. While it may have
some miscibility properties with mineral-based oil
and POE oil (Polyolester), it is not recommended to
mix PVE oil with any other type of refrigerant oil.
IMPORTANT
Always use two wrenches when tightening flare
nuts to avoid twisting refrigerant piping. DO
NOT over-tighten flare nuts.
NOTE -
Always slide a flare nut onto the field-
provided refrigerant piping before flaring the lines.
1. The seal on the unit refrigerant piping connections
should remain in place until the last possible
moment. This will prevent dust or water from
getting into the refrigerant piping before it is
connected.
2.
Remove the flare nuts from the connections on
the unit and discard the seal from each of the
piping connections.
3. Slide the flare nuts onto the ends of the field-
provided refrigerant piping before using a suitable
flaring tool to flare the end of the copper pipe.
4. Apply recommended R-410A refrigerant lubricant
to the outside of the flared refrigerant lines
(Figure 19-A).
To Outdoor unit
To Indoor Unit
Backup
Wrench
Torque
Wrench
Summary of Contents for VPB H4-3P Series
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