Carrier 48LJD - Manual (Page 11)

TWO-POSITION DAMPER - The outdoor-air hood and
screen are attached to the basepan at the bottom of the unit.
Assembly:
1. Determine quantity of ventilation air required for build­
ing. Record amount of air for use in Step 9.
2. Remove and save evaporator coil access panel and screws.
See Fig. 16.
3. Separate hood from basepan by removing the 4 screws
securing the hood. Save screws.
4. Insert two-position damper plug from wiring harness
(supplied with the unit) into the wiring harness (sup­
plied with the two-position damper).
5. Replace evaporator coil access panel.
6. Place hood on front of evaporator coil access panel.
See Fig. 13 for hood details. Secure top of hood with
the 4 screws removed in Step 3. See Fig. 14.
EVAPORATOR
COIL ACCESS
PANEL
BLOCK-OFF------ '
PANEL
m m
Fig. 17 — Access Panel Location
i
EVAPORATOR
COIL ACCESS
PANEL
SCREW
HOLES
(SIDE)
OUTDOOR-AIR
ADJUSTMENT
SCREWS
POSITION
SETTING SCALE
Fig. 16 — Damper Panel with Two-Position
Damper Installed
7. Remove and save 6 screws (3 on each side) from sides
of the two-position damper.
8. Align screw holes on hood with screw holes on side of
two-position damper. See Fig. 13 and 14. Secure hood
with 6 screws from Step 7.
9. Determine two-position damper setting by using
Fig. 15. Set the damper panel position using the air ad­
justment screws. See Fig. 16. Tighten screws.
10. Remove and save 4 screws currently on sides of hood.
Insert screen. Secure screen to hood using the 4 screws.
See Fig. 14.
OPTIONAL ECONOMIZER — The economizer hood as­
sembly is packaged and shipped in the filter section. Damper
blades are installed at the factory and the economizer is shipped
in the vertical position.
Assembly:
1. Determine quantity of ventilation air required for build­
ing. Record amount of air for use in Step 8.
2. Remove evaporator coil access panel (see Fig. 17). Save
panel and screws.
3. Assemble outdoor-air hood top and side plates as shown
in Fig. 18. Install seal strips on hood top and sides. Put
aside screen retainer and screws for later assembly. Do
not attach hood to unit at this time.
4. The block-off panel should be removed from the evap­
orator coil access panel and discarded. Save screws.
See Fig. 17.
HOOD SIDES AND TOP ASSEMBLED
Fig. 18 — Outdoor-Air Hood Details
5. Remove screws securing barometric relief damper, if
desired. See Fig. 19.
6. To convert to horizontal discharge application:
a. Remove filters from filter track.
IMPORTANT: Filters must be installed outside the
unit on horizontal discharge applications with econo­
mizer. Otherwise, economizer must be partially re­
moved to access the filters. The area of the field-
installed filters should be equal to the area of the factory-
installed filters.
b.
c.
Rotate economizer 90 degrees until economizer mo­
tor faces condenser section (see Fig. 20). If neces­
sary, disassemble economizer to replace filter.
Rotate barometric relief damper 90 degrees so that it
opens and closes vertically.
11