10
• When installed in areas where low ambient tem-
peratures exist, locate unit so winter prevailing
winds do not blow directly on to the outdoor unit.
Air Discharge Duct
•
Before installing the air duct, remove the two fan
guards from the top of the unit.
• Duct each outdoor unit separately. Do not use
a combined plenum as this may result in air not
being discharged directly to the outside.
• Discharge air duct shall be constructed of steel
and installed in a manner which prevents sagging
and or collapsing.
• Only one bend is allowed in the air duct.
•
Duct louvers will reduce air volume, cooling and
heating capacity and efficiency. Louvers are not
recommended; if they are required by the job,
the louver angle should be no larger than 15°.
•
It may be necessary to install a flexible connector
between the unit and the duct to reduce vibration
noise.
Static Pressure
Description
0 WG (0 Pa)
Default
0-0.08 WG (0-20
Pa)
Remove fan guard, < 10 ft. (3 m)
duct length
Above 0.08 WG
(20 Pa)
Contact Lennox VRF Applications
Support
NOTE -
Use dip switch S4 to change outdoor
unit static pressure settings.
Table 1. Static Pressure Settings
llation
Wrong Installation
Rear
Front
Inlet
Wind
Wrong Installation
Rear
Front
Outlet
Wind
Figure 9. Protect Unit from Prevailing Winds
Rear
Front
Outlet
Wind
Correct Installation
Summary of Contents for VPB Series
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