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for Y2 In, the 2-speed fan delay starts and the OA damper will
modulate 100% open, the supply fan should be set to high
speed by the unit controller. After the delay one of two actions
will happen:
• The Y2 In call will be satisfied with the damper 100% open
and fan on high speed and the call will turn off.
OR
• If the call for additional cooling in the space has not been
satisfied then the first stage of mechanical cooling will be
enabled through Y1 Out or Y2 Out.
Indoor Air Quality AQ
Indoor Air Quality (indoor sensor input): Terminal AQ accepts a
+2 to +10 Vdc signal with respect to the (AQ1) terminal. When
the signal is below it's set point, the actuator is allowed to
modulate normally in accordance with the enthalpy and mixed
air sensor inputs. When the AQ signal exceeds it's set point
setting and there is no call for free cooling, the actuator is
proportionately modulated from the 2 to 10 Vdc signal, with 2
Vdc corresponding to full closed and 10 Vdc corresponding to
full open. When there is no call for free cooling, the damper
position is limited by the IAQ Max damper position setting.
When the signal exceeds it's set point (Demand Control
Ventilation Set Point) setting and there is a call for free cooling,
the actuator modulates from the minimum position to the full
open position based on the highest call from either the mixed
air sensor input or the AQ voltage input.
• Optional CO
Space Sensor Kit Part # 2AQ04700324
2
• Optional CO
Sensor Kit Part # 2AQ04700424
2
Replace the top rear access panel on the unit.
Phasing
®
Predator
units are properly phased at the factory. Check for
proper compressor rotation. If the blower or compressors rotate
in the wrong direction at start-up, the electrical connection to
the unit is misphased. Change the phasing of the Field Line
Connection at the factory or field supplied disconnect to
obtain proper rotation. (Scroll compressors operate in only one
direction. If the scroll is drawing low amperage, has similar
suction and discharge pressures, or producing a high noise
level, the scroll is misphased.)
Scroll compressors require proper rotation to operate
correctly. Units are properly phased at the factory. Do
not change the internal wiring to make the blower
condenser fans, or compressor rotate correctly.
Johnson Controls Unitary Products
Blower Rotation
Check for proper supply air blower rotation. If the blower is
rotating backwards, the line voltage at the unit point of power
connection is misphased (See 'PHASING').
Table 14: Supply Air Limitations
Unit Size (Ton)
078 (6.5)
090 (7.5)
102 (8.5)
120 (10)
150 (12.5)
Belt Tension
The tension on the belt should be adjusted as shown in Figure 30.
A
C*
* NEVER LOOSEN
A
B
Figure 30: Belt Adjustment
860614-YIM-D-0614
Minimum
Maximum
1950
3250
2250
3750
2550
4250
3000
5000
3750
6250
A
SPAN LENGTH
DEFL. FORCE
39
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