Direct Drive; Outdoor Hoods And Louvers - Carrier AERO 39MN Installation, Start-Up And Service Instructions Manual

after unit reaches operating speed. Excessive belt tension
shortens belt life and may cause bearing and shaft damage.
After run-in, set belt tension at lowest tension at which
belts will not slip during operation.
Direct drive fans are aligned in the factory,
Direct Drive —
however, Carrier recommends checking alignment before start-
ing the unit.
1. Ensure the radial distance between fan wheel and inlet
cone appears visually equal in all directions.
2. Ensure that the fan wheel to inlet cone overlap is within the
range given in the table.
3. Motor and fan are balanced as an assembly. If either chang-
es, rebalancing is required.
CAUTION
Do not exceed maximum fan speed rpm with variable fre-
quency drive.
Outdoor Hoods and Louvers —
tions available: fixed rear intake hoods, intake louvers, and
collapsible exhaust box hoods. All hoods and louvers have an
intake screen to prevent unwanted entry of birds and debris.
The intake hoods have easily serviceable demisters via small
hinged doors. Intake louvers are a wind driven rain design
that will allow no more than .01 oz per sq ft of free area water
penetration at 1250 fpm. This is the maximum velocity re-
quired by AMCA (Air Movement and Control Association)
511. Higher velocities are possible without significant water
intrusion.
Most fixed rear hoods (Fig. 38) and intake louvers
(Fig. 39) ship installed and should require no further
assembly. If a rear hood is shipped attached to the skid, do not
NOTE: All dimensions in inches unless otherwise noted.
There are three op-
GASKET
0.125 THICK x 1.25 WIDE
LOUVER
ASSEMBLY
INSERT HOOKS THROUGH
HOLES TO LIFT LOUVER
ASSEMBLY INTO PLACE
SCREW
1/4-14 x 3/4 SNS
Fig. 39 — Intake Louver
install the rear hood in the air-handling until the rest of the
unit and splits have been completely assembled. Otherwise,
the combination of just the hood and mixing box may become
a tipping hazard.
Fig. 38 — Rear Intake Hood (Size 30 Shown)
Collapsible exhaust box hoods ship covering the exhaust
outlet of the unit and/or inside the unit and require some basic
assembly. Fasteners, washers and gasket material for installa-
tion of the hood come taped inside the exhaust section. Figure
40 shows an exploded view of the assembly in its shipping
position. Figure 40 shows how the various parts assemble to
form the hood and a view of the completed assembly.
IMPORTANT: Hoods for power exhaust fans must be field
supplied based on local code requirements.
69
UNIT
GASKET
SCREW TYPICAL
ENTIRE PERIPHERY
INTAKE HOOD
A39-2347
OPEN DOOR TO
REMOVE DEMISTERS
a39-4234