16
17
920-138-02 (3-04)
920-138-02 (3-04)
Damper Linkage Ball
Shaft
Exhaust Air Damper
Damper Motor
Shaft
Damper, Motor Mount
Sensor
Figure 14
Factory Installed Economizer Components
Side View
Economizer (XE)
General Descrption
The economizer provides free cooling when outside conditions
are cool and dry enough to satisfy cooling requirements and
it is not necessary for the compressor to run. Between 0%
and 100% outside air can be introduced. A built-in exhaust
air damper provides pressure relief.
Operation
The economizer will determine if outside air is suitable for
free cooling. If the outside air is suitable for free cooling the
economizer will open and modulate blade position automatically
and maintain 55F supply air temperature. If the outside air is not
suitable for free cooling the economizer remains closed and
energizes the compressor for cooing operation.
Adjustment
(1 1⁄2 - 5 Ton Chassis)
1) (Step 1 & 2 for 1 1⁄2 - 3 ton models only) Through
the return air opening, remove two (2) screws on
the access cover under the blade.* (The minimum
position is set from the factory to open the Economizer
enough to remove access cover. The Economizer
must be energized to allow the blade to open.)
2) Remove the access cover.
3) The enthalpy control is visible through the access
opening. Using the chart on page 17, determine the
proper enthalpy setting. Adjust the controller to the
desired setting using a small flat blade screwdriver.
(Factory enthalpy setting is the “D” position.)
4) Re-install access cover and two (2) screws.
*3 1⁄2 - 5 ton chassis adjustment does not require the access
cover to be removed all adjustments are made through the
return air opening.
Figure 15
Return Air Opening
Access Cover
A
B
C
D
Return Air Opening
Access Cover
Access Cover Removed
Access Cover Installed
Enthalpy
Adjustment
Summary of Contents for OES Series
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