25
Outdoor air leakage is shown in Table 9. Return air pressure
drop is shown in Table 10.
Table 9 — Outdoor Air Damper Leakage
Table 10 — Return Air Pressure Drop (in. wg)
ECONOMI$ERIV STANDARD SENSORS
Outdoor Air Temperature (OAT) Sensor — The outdoor air
temperature sensor (HH57AC074) is a 10 to 20 mA device
used to measure the outdoor-air temperature. The outdoor air
temperature is used to determine when the EconoMi$erIV can
be used for free cooling. The sensor must be field-relocated.
See Fig. 33. The operating range of temperature measurement
is 40 to 100 F.
Supply Air Temperature (SAT) Sensor — The supply air
temperature sensor is a 3 K thermistor located at the inlet of the
indoor fan. See Fig. 34. This sensor is factory installed. The op-
erating range of temperature measurement is 0° to 158 F. See
Table 11 for sensor temperature/resistance values.
The temperature sensor looks like an eyelet terminal with
wires running to it. The sensor is located in the “crimp end”
and is sealed from moisture.
Low Temperature Compressor Lockout Switch — The Econo-
Mi$erIV is equipped with an ambient temperature lockout
switch located in the outdoor airstream which is used to lockout
the compressors below a 42 F ambient temperature. See Fig. 33.
Table 11 — Supply Air Sensor Temperature/
Resistance Values
DAMPER STATIC PRESSURE (in. wg)
0.2 0.4 0.6 0.8 1.0 1.2
LEAKAGE (cfm) 35 53 65 75 90 102
CFM
4500 5000 5400 6000 7200 7500 9000 10,000 11,250
0.040 0.050 0.060 0.070 0.090 0.100 0.110 0.120 0.140
TEMPERATURE (F) RESISTANCE (ohms)
–58 200,250
–40 100,680
–22 53,010
–4 29,091
14 16,590
32 9,795
50 5,970
68 3,747
77 3,000
86 2,416
104 1,597
122 1,080
140 746
158 525
176 376
185 321
194 274
212 203
230 153
248 116
257 102
266 89
284 70
302 55
ECONOMI$ERIV
OUTDOOR AIR
TEMPERATURE SENSOR
(INSTALLED OPERATION
POSITION)
SCREWS
SCREWS FRAME
TOP
LOW TEMPERATURE
COMPRESSOR
LOCKOUT SWITCH
ACTUATOR
ECONOMI$ERIV
FLANGE
AND SCREWS
(HIDDEN)
CONTROLLER
SUPPLY AIR
TEMPERATURE SENSOR
LOCATION
TR1
24 Vac
COM
TR
24
Vac
HOT
12
34
5
EFEF1
+_
P1
T1
P
T
N
EXH
2V1
0V
EXH
Set
Set
2V1
0V
2V10V
DCV
DCV
Free
Cool
BC
AD
SO+
SR+
SR
SO
AQ1
AQ
DCV
Min
Pos
Open
Max
N1
Fig. 33 — EconoMi$erIV Component Locations —
End View
Fig. 34 — EconoMi$erIV Component Locations —
Side View
FRAME
TOP
SCREWS
ECONOMI$ER2 SCREWS
Fig. 35 — EconoMi$er2 Component Locations