Filter
Top Products
9. Remove and save screws currently on sides of hood.
Insert screens. Secure screens to hood using the screws.
See Fig. 16.
10. Replace filter access panel. Ensure filter access panel
slides along the tracks and is securely engaged.
OPTIONAL DURABLADE ECONOMIZER — The op-
tional economizer hood assembly is packaged and shipped
in the filter section. Damper blades and control boards are
installed at the factory and the economizer is shipped in the
vertical discharge position.
NOTE: Horizontal discharge block-off plate is shipped with
the air hood package. If unit is to be used for vertical dis-
charge application, discard this plate.
Assembly
1. Determine if ventilation air is required in building. If
so, determine the minimum amount to be supplied by
each unit and record quantity of ventilation air needed
for use in Step 8.
2. Remove filter access panel by raising panel and swing-
ing panel outward. Panel is now disengaged from track
and can be removed. No tools are required to remove
filter access panel. Remove outdoor-air opening panel.
Save panels and screws. See Fig. 18. Remove optional
economizer and outdoor-air damper hood package from
filter section.
3. Assemble outdoor-air hood top and side plates as shown
in Fig. 19. Install seal strips on hood top and sides. Put
aside screen retainer and retainer screw for later assem-
bly. Do not attach hood to unit at this time.
4. On 012 and 014 units, install vertical discharge block-
off plate over duct openings. See Fig. 20.
5. Slide economizer into unit and secure with screws. See
Fig. 21.
NOTE: Be sure to engage rear economizer flange under
tabs in vertical return-air opening.
6. To convert to horizontal discharge application:
a. Rotate the economizer 90 degrees until the econo-
mizer motor faces the condenser section (see
Fig. 22).
b. Rotate the barometric relief damper hinge
90 degrees. Barometric relief damper should open ver-
tically to operate properly.
c. Install horizontal discharge block-off plate over the
opening on the access panel. (Block-off plate MUST
be installed before installing hood assembly.) See
Fig. 23.
7. Insert economizer plug into economizer harness. Re-
move tape from barometric relief damper. See Fig. 21.
8. If ventilation air is not required, proceed to Step 9. If
ventilation air is required, determine the minimum po-
sition setting for required airflow. See Fig. 24. Adjust
minimum position setting by adjusting the screws on the
position setting bracket. See Fig. 25. Slide bracket until
the top screw is in the position determined by
Fig. 24. Tighten screws.
9. Remove tape from outdoor-air thermostat (OAT). Fas-
ten OAT to inside of hood using screws and speed clips
provided. See Fig. 26. Make sure OAT terminals are po-
sitioned up.
10. Replace outdoor-air opening panel using screws from
Step 2. Replace filter access panel. Ensure the filter ac-
cess panel slides along the tracks and is securely
engaged.
11. Fasten hood top and side plate assembly to outdoor-air
opening panel with screws provided.
12. Place knob supplied with economizer on OAT. See
Fig. 26. Set for 3° F below indoor room thermostat set-
ting. If accessory enthalpy control (EC) is used in place
of OAT, see instructions shipped with EC for installa-
tion and adjustment. See Fig. 26.
13. Connect OAT per Fig. 27.
14. Slide outdoor-air inlet screens into screen track on hood
side plate. While holding screens in place, fasten screen
retainer to hood using screws provided.
NOTE: Refer to Fig. 28 for Durablade economizer baromet-
ric relief damper characteristics.
Fig. 17 — Position Setting
OUTDOOR-AIR
OPENING PANEL
FILTER ACCESS
PANEL
Fig. 18 — Access Panel Locations
12