2
INSTALLER’S GUIDE
4. Install Economizer Assembly
1. The economizer ships with the return air damper folded
up to allow the assembly to fit through the Coil opening
in the side of the unit. Insert the economizer assembly
into the unit through the Coil access panel opening. See
Figure 4 on page 4.
2. Swing the return air damper section down so that it
rests on the bottom of the unit. The economizer will sit
completely over the return air opening in the bottom of
the unit. See Figure 5 on page 4. Screw the economizer
assembly together with one assembly screw in the side
of the economizer. Check the linkage rod between the
return air dampers to make sure it is tight.
3. Insert 2 screws through the holes in the front face of the
unit and into the matching attachment holes in the econo-
mizer assembly. See Figure 6 on page 5.
4. Insert a screw through the pre-punched hole in the side
flange of the return air damper and into the mating hole
in the economizer assembly and tighten. See Figure 5 on
page 4.
Use care when inserting the economizer in the return
air compartment, to prevent damaging the foil faced
insulation.
CAUTION
5. Install Rain Hood Assembly
1. Locate the rainhood assembly, which includes the relief
damper and the mist eliminator. The back of the hood side
mating flanges need to be gasketed (gaskets included in
kit). Loosen the right two (2) screws on the unit’s top seal
-
ing flange above the economizer. See Figure 7 on page
5.
2. S
lide the top flange of the hood underneath the unit’s top
sealing flange. Drive two self tapping screws into the key
-
hole openings on the side flanges of the hood. Tighten the
two (2) screws on the top sealing flange and the screws
on the hood side flanges. See Figures 7 and 9.
6. Mount Mixed Air Sensor
1. Mount the Mixed Air sensor (with wiring) to the left
Blower partition using two sheetmetal screws. See
Figure 10, page 7. The male tabs on the Yellow and
Yellow/Black wires will connect to the Economizer wiring
harness in a later step.
2. Enthalpy Sensor If used, install this option at this time per
instructions provided in the sensor kit.
7. Route Main Wiring
1. From the Economizer assembly, pass the wire harness
through the coil grommet. See Figure 11 (view A) on page
7. Continue routing the harness behind the Compressor
compartment and into the Blower compartment.
2. Continue routing the remaining harness through the grom-
met in the Control Box partition and into the Control Box.
8. Complete Installation
(4WCZ6, 4DCZ6, 4YCZ6)
1. In the Control Box, locate the ICMC Board in the upper
left hand corner of the Control Box. Find the YL/RD and
YL wires in the 12 pin connector. Leaving enough length
of these wires so that the ends going to the ICMC Board
can be stripped, cut these wires in two. Strip the cut end
of the wires going to the ICMC Board and connect to
economizer wires as per hookup diagrams on pages 8
and 9. Cap the ends of the Yellow and Yellow/Red wires
not being hooked up. Secure all wires with wire ties so
that there is no interference with any moving parts in the
unit.
2. In the Control Box, complete the wiring connections per
the appropriate wiring diagram on pages 8 and 9. Secure
all wires so that there is no interference with any moving
parts in the unit.
3. P
ower the economizer and run the checkout procedure
on page 10. Make desired adjustments to the control
-
ler setting the minimum occupied damper position, the
outside air setting (if enthalpy control used).
4. Replace the unit Coil access panel, the Blower access
panel, and the Control/Heat access panel.
Be certain to cap the ends of the cut YL/RD and YL
wires that are not being connected to an accessory
or the unit to reduce the risk of a short.
CAUTION
NOTE:
You must install the filter rack per the instructions
provided with the filter rack after you install the economizer.
