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4. Connect 24 vac across terminals TR and TR1.
5. Carefully adjust the minimum position potentiometer
until the measured mixed-air temperature matches the
calculated value.
6. Reconnect the supply air sensor to terminals T and T1.
Remote control of the EconoMi$er IV damper is desirable
when requiring additional temporary ventilation. If a field-
supplied remote potentiometer (Honeywell part number
S963B1128) is wired to the EconoMi$er IV controller, the
minimum position of the damper can be controlled from a
remote location.
To control the minimum damper position remotely, remove
the factory-installed jumper on the P and P1 terminals on the
EconoMi$er IV controller. Wire the field-supplied potentiome-
ter to the P and P1 terminals on the EconoMi$er IV controller.
See Fig. 36.
Damper Movement — Damper movement from full open to
full closed (or vice versa) takes 2
Thermostats — The EconoMi$er IV control works with con-
ventional thermostats that have a Y1 (cool stage 1), Y2 (cool
stage 2), W1 (heat stage 1), W2 (heat stage 2), and G (fan). The
EconoMi$er IV control does not support space temperature
sensors. Connections are made at the thermostat terminal con-
nection board located in the main control box.
Occupancy Control — The factory default configuration for
the EconoMi$er IV control is occupied mode. Occupied status
is provided by the black jumper from terminal TR to terminal
N. When unoccupied mode is desired, install a field-supplied
timeclock function in place of the jumper between TR and N.
See Fig. 28. When the timeclock contacts are closed, the
EconoMi$er IV control will be in occupied mode. When the
timeclock contacts are open (removing the 24-v signal from
terminal N), the EconoMi$er IV will be in unoccupied mode.
Demand Controlled Ventilation (DCV) — When using the
EconoMi$er IV for demand controlled ventilation, there are
some equipment selection criteria which should be considered.
When selecting the heat capacity and cool capacity of the
equipment, the maximum ventilation rate must be evaluated for
design conditions. The maximum damper position must be cal-
culated to provide the desired fresh air.
Typically the maximum ventilation rate will be about 5 to
10% more than the typical cfm required per person, using
normal outside air design criteria.
A proportional anticipatory strategy should be taken with
the following conditions: a zone with a large area, varied occu-
pancy, and equipment that cannot exceed the required ventila-
tion rate at design conditions. Exceeding the required ventila-
tion rate means the equipment can condition air at a maximum
ventilation rate that is greater than the required ventilation rate
for maximum occupancy. A proportional-anticipatory strategy
will cause the fresh air supplied to increase as the room CO
level increases even though the CO
reached. By the time the CO
damper will be at maximum ventilation and should maintain
the set point.
In order to have the CO
damper in this manner, first determine the damper voltage out-
put for minimum or base ventilation. Base ventilation is the
ventilation required to remove contaminants during unoccu-
pied periods. The following equation may be used to determine
the percent of outside-air entering the building for a given
damper position. For best results there should be at least a
10 degree difference in outside and return-air temperatures.
OA
RA
(T
x
) + (TR x
) = T
O
100
100
T
= Outdoor-Air Temperature
O
OA = Percent of Outdoor Air
1
/
minutes.
2
set point has not been
2
level reaches the set point, the
2
sensor control the economizer
2
M
T
= Return-Air Temperature
R
RA = Percent of Return Air
T
= Mixed-Air Temperature
M
Once base ventilation has been determined, set the mini-
mum damper position potentiometer to the correct position.
The same equation can be used to determine the occupied or
maximum ventilation rate to the building. For example, an out-
put of 3.6 volts to the actuator provides a base ventilation rate
of 5% and an output of 6.7 volts provides the maximum venti-
lation rate of 20% (or base plus 15 cfm per person). Use Fig. 39
to determine the maximum setting of the CO
ample, a 1100 ppm set point relates to a 15 cfm per person de-
sign. Use the 1100 ppm curve on Fig. 39 to find the point when
the CO
sensor output will be 6.7 volts. Line up the point on
2
the graph with the left side of the chart to determine that the
range configuration for the CO
The EconoMi$er IV controller will output the 6.7 volts from
the CO
sensor to the actuator when the CO
2
the space is at 1100 ppm. The DCV set point may be left at 2
volts since the CO
EconoMi$er IV controller until it rises above the 3.6 volt set-
ting of the minimum position potentiometer.
Once the fully occupied damper position has been deter-
mined, set the maximum damper demand control ventilation
potentiometer to this position. Do not set to the maximum posi-
tion as this can result in over-ventilation to the space and poten-
tial high-humidity levels.
CO
Sensor Configuration — The CO
2
standard voltage settings that can be selected anytime after the
sensor is powered up. See Table 7.
Use setting 1 or 2 for Carrier equipment. See Table 7.
1. Press Clear and Mode buttons. Hold at least 5 seconds
until the sensor enters the Edit mode.
2. Press Mode twice. The STDSET Menu will appear.
3. Use the Up/Down button to select the preset number. See
Table 7.
4. Press Enter to lock in the selection.
5. Press Mode to exit and resume normal operation.
The custom settings of the CO
time after the sensor is energized. Follow the steps below to
change the non-standard settings:
1. Press Clear and Mode buttons. Hold at least 5 seconds
until the sensor enters the Edit mode.
2. Press Mode twice. The STDSET Menu will appear.
3. Use the Up/Down button to toggle to the NONSTD menu
and press Enter.
4. Use the Up/Down button to toggle through each of the
nine variables, starting with Altitude, until the desired set-
ting is reached.
2
5. Press Mode to move through the variables.
6. Press Enter to lock in the selection, then press Mode to
continue to the next variable.
Dehumidification of Fresh Air with DCV Control — Infor-
mation from ASHRAE indicates that the largest humidity load
on any zone is the fresh air introduced. For some applications,
a device such as a 62AQ energy recovery unit is added to re-
duce the moisture content of the fresh air being brought into the
building when the enthalpy is high. In most cases, the normal
heating and cooling processes are more than adequate to re-
move the humidity loads for most commercial applications.
If normal rooftop heating and cooling operation is not ade-
quate for the outdoor humidity level, an energy recovery unit
and/or a dehumidification option should be considered.
28
sensor. For ex-
2
sensor should be 1800 ppm.
2
concentration in
2
sensor voltage will be ignored by the
2
sensor has preset
2
sensor can be changed any-
2
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