19
Mount the return air enthalpy sensor in the return air duct.
The return air enthalpy sensor is wired to terminals S
R
and + on
the EconoMi$er2 controller. See Fig. 31. The outdoor enthalpy
changeover set point is set with the outdoor enthalpy set point
potentiometer on the EconoMi$er2 controller. Turn the potenti-
ometer to the D setting for differential enthalpy. See Fig. 32.
Indoor Air Quality Sensor Input (ISI) — The ISI can be used
for any indoor air quality sensor that provides a 2 to 10 vdc out-
put. The controller will modulate the outdoor damper to pro-
vide ventilation based on the sensor output and the setting of
the ISI potentiometer. The ISI LED will be lit when the ISI sig-
nal is above the ISI potentiometer set point.
A separate field-supplied transformer must be used to pow-
er the CO
2
sensor.
Mount the optional indoor air quality (CO
2
) sensor accord-
ing to manufacturer specifications. The CO
2
sensor should be
wired to the AQ and AQ1 terminals of the controller. Adjust
the ISI potentiometer to correspond to the ISI voltage output of
the indoor air quality sensor at the user-determined set point.
See Fig. 25.
17 1/4”
DIVIDER
BAROMETRIC
RELIEF
CLEANABLE
ALUMINUM
FILTER
FILTER
HOOD
FILTER
CLIP
OUTSIDE
AIR
Fig. 24 — Filter Installation
+
+
+
+
+
-
-
-
2-10V
OUT
RED
RUN
BLACK
WHITE
24 VAC HOT
TR
BLACK
BROWN
BROWN
BLACK
BLACK
GRAY
BLUE
YELLOW
VIOLET
VIOLET
VIOLET
PINK
PINK
RED
WHITE
WHITE
BROWN
ORANGE
620 OHM
RESISTOR
820 OHM
RESISTOR
SO
NOTE 8
5
1
3
1K
1S
1S1
2K
2
4
T
P
P1
Q
Q1
AQ
SD1
SD
AC
AC1
PG
PG1
ECONOMIZER
DRY BULB
SENSOR
Compressor Lockout N.C.
YELLOW
GRAY
BLUE
TAN
INDOOR
FAN
EXHAUST
FAN
UNIT
CONTROL
FREE
COOL
MAXIMUM
POSITION
ADJUSTMENT
2-10 VDC
CO2 SENSOR
HARNESS
AND PLUG
MINIMUM
POSITION
ADJUSTMENT
AQ1
T1
SR
TR1
24 VAC COM
ACTUATOR
4
3
5
2
8
6
7
1
10
11
9
12
}
NOTE 9
NOTE 6
NOTE 1
NOTE 5
NOTE 7
NOTE 2
NOTE 4
NOTE 3
ECONOMISER2 CONTROLLER
NOTES:
1. The standard EconoMi$er2 is shipped with a fixed dry bulb sensor. (Open 67 F — Close 52 F.) An adjustable dry bulb or enthalpy sensor can
replace the fixed dry bulb. (See Note 6.)
2. CO
2
sensor is optional. Field-installed accessory. See rooftop price pages for ordering data and pricing. Power for CO
2
sensor should be pro-
vided by field-supplied transformer.
3. The HVAC unit is shipped with a jumper plug attached to the EconoMi$er2 harness. Remove the jumper plug and save for future use if econo-
mizer is removed. Connect the male side of plug (shown above) to the female side in HVAC unit.
4. 1S is an electronic switch that closes when powered by a 24 vac input.
5. Factory-installed 620-ohm, 1 watt, 5% resistor should be removed only when a HH57AC078 enthalpy sensor or CROASENR001A00 adjust-
able dry bulb is added to SR and + for differential sensing.
6. When replacing the fixed dry bulb sensor with an enthalpy or adjustable dry bulb, remove the 820-ohm resistor.
7. Compressor lockout (Open 35 F — Close 50 F).
8. See EconoMi$er2 Installation Instructions for details on locating and wiring supply air (mixed air) sensor.
9. Switch on actuator must be in run position for economizer to operate.
10. A 2-stage thermostat is recommended.
Fig. 25 — EconoMi$er2 Wiring
Summary of Contents for 48TF004-007
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