Envision Peripherals Series - Manual (Page 19)

17
NS SPLIT INSTALLATION MANUAL
The Envision series comes with a holding charge. The charge must be adjusted in the field based on performance.
Refrigeration piping on the split consists of installing a brazed copper line set between the blower coil unit and the unit’s split
compressor section. To select the proper tube diameters for the installation, refer to the table on page 9. Line sets over 60
feet long are not recommended because of oil return and pressure drop problems. The suction line must always be insu-
lated. Handle and route the line sets carefully to avoid kinking or bending the tubes. If the line set is kinked or distorted and
it cannot be formed back into its original shape, the bad portion of the pipe should be replaced. A restricted line set will affect
the performance of the system.
Connection to Air Coil
Figures 1 and 2 illustrate typical Envision Split installations. The table on page 9 shows typical lineset diameters and
maximum length. As in all R-410A equipment, a reversible liquid line filter drier is required to insure all moisture is removed
from the system. This drier should be replaced whenever “breaking into” the system for service. All linesets should be
insulated with a minimum of 1/2” closed cell insulation. All insulation should be painted with UV resistant paint or covering to
insure long insulation life.
Fasten the copper line set to the blower coil unit as instructed by the coil installation instructions. Nitrogen should be bled
through the system at 2 to 3 PSI to prevent oxidation inside the refrigerant tubing. Use a low silver phos-copper braze alloy
on all brazed connections.
Braze line set to the service valve stubs on the
inside front of the split cabinet as shown in Figure 7.
Nitrogen should be bled through the system at 2 to
3 PSI to prevent oxidation contamination. Use a low
silver phos-copper braze alloy on all brazed connec-
tions. Envision split units are shipped with a factory
charge and service valves are not to be opened
until the line set has been leak tested, purged and
evacuated. Schrader cores should be removed
before brazing. A heat sink should be used on the
service valves and TXV to prevent damage caused
by excessive heat.
Refrigeration
Replace caps after
opening system
Service ports for
attaching refrigerant
gauges
Insulated
Suction Line
Braze
Connection
Liquid
Line
ccw
ccw
Figure 7: Typical Split System Refrigerant Line Connections