Step 7 - Adjust Indoor-Fan Speed - Carrier 50TFQ008-012 Installation, Start-Up And Service Instructions Manual

CO sensor to the actuator when the CO
2
space is at 1100 ppm. The DCV set point may be left at 2 volts
since the CO sensor voltage will be ignored by the
2
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 8.
Use setting 1 or 2 for Carrier equipment. See Table 8.
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 8.
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.
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
SETTING EQUIPMENT
1
Interface w/Standard
2
Building Control System
3
4
5
Economizer
6
7
8 Health & Safety
Parking/Air Intakes/
9
Loading Docks
LEGEND
ppm — Parts Per Million
concentration in the
2
sensor has preset
2
sensor can be changed any-
2
Table 8 — CO Sensor Standard Settings
2
VENTILATION
OUTPUT RATE
(cfm/Person)
Proportional Any
Proportional Any
Exponential Any
Proportional 15
Proportional 20
Exponential 15
Exponential 20
Proportional —
Proportional —
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.
Step 7 — Adjust Indoor-Fan Speed —
indoor-fan speed to meet jobsite conditions.
For units with electric heat, required minimum cfm is 2250
for 50TFQ008, 2550 for 50TFQ009 and 3000 for 50TFQ012
with the following exceptions:
UNIT
UNIT
VOLTAGE
208/230
208/230
50TFQ012 460
575
Table 9 shows indoor-fan motor data. Table 10 shows fan
rpm at motor pulley settings for standard and alternate motors.
Tables 11A and 11B show static pressure for accessories. Refer
to Tables 12-27 to determine fan speed settings. Fan motor
pulleys are factory set for speed shown in Table 1.
To change fan speeds:
1. Shut off the unit power supply and tag disconnect.
2. Loosen the belt by loosening the fan motor mounting
nuts. See Fig. 38 and 39.
3. Loosen the movable pulley flange setscrew (see Fig. 40).
4. Screw the movable flange toward the fixed flange to
increase speed or away from the fixed flange to decrease
speed. Increasing the fan speed increases the load on the
motor. Do not exceed the maximum speed specified in
Table 1.
5. Set the movable flange at nearest keyway of the pulley
hub and tighten the setscrew. (See Table 1 for speed
change for each full turn of the pulley flange.)
CO
2
ANALOG
CONTROL RANGE
OUTPUT
(ppm)
0-10V
0-2000
4-20 mA
2-10V
0-2000
7-20 mA
0-10V
0-2000
4-20 mA
0-10V
0-1100
4-20 mA
0-10V
0- 900
4-20 mA
0-10V
0-1100
4-20 mA
0-10V
0- 900
4-20 mA
0-10V
0-9999
4-20 mA
0-10V
0-2000
4-20 mA
25
Adjust the
UNIT REQUIRED
HEATER
CONFIG- MINIMUM
kW
URATION CFM
42.4 Horizontal 3200
50.0 Horizontal 3200
Horizontal or
50.0 3200
Vertical
17.0 2800
Horizontal or
Vertical
51.0 2350
OPTIONAL RELAY
RELAY SETPOINT HYSTERESIS
(ppm) (ppm)
1000 50
1000 50
1100 50
1100 50
900 50
1100 50
900 50
5000 500
700 50