Carrier CRECOMZR052A00 - Dehumidification of Fresh Air with DCV Control

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3. Use the Up/Down button to select the preset number. (See
Table 5.)
4. Press Enter to lock in the selection.
5. Press Mode to exit and resume normal operation.
The custom settings of the CO
2
sensor can be changed anytime
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 enter 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 setting 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
Information from ASHRAE indicates that the largest humidity
load on any zone is the fresh air introduced. For some application,
an energy recovery unit can be added to reduce 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 remove the humidity loads
for most commercial applications. If normal rooftop heating and
cooling operation is not adequate for the outdoor humidity level,
and energy recovery unit and/or a dehumidification option should
be considered.
LEGEND
ppm — Parts Per Million
Table 5 — CO
2
Sensor Standard Settings
SETTING EQUIPMENT OUTPUT
VENTILATION
RATE
(cfm/Person)
ANALOG
OUTPUT
CO
2
CONTROL
RANGE
(ppm)
OPTIONAL
RELAY
SETPOINT
(ppm)
RELAY
HYSTERESIS
(ppm)
1
Interface w/Standard
Building Control
System
Proportional Any
0-10V
4-20 mA
0-2000 1000 50
2 Proportional Any
2-10V
4-20 mA
0-2000 1000 50
3 Exponential Any
0-10V
4-20 mA
0-2000 1100 50
4
Economizer
Proportional 15
0-10V
4-20 mA
0-1100 1100 50
5 Proportional 20
0-10V
4-20 mA
0-900 900 50
6 Exponential 15
0-10V
4-20 mA
0-1100 1100 50
7 Exponential 20
0-10V
4-20 mA
0- 900 900 50
8 Health and Safety Proportional —
0-10V
4-20 mA
0-9999 5000 500
9
Parking/Air Intakes/
Loading Docks
Proportional —
0-10V
4-20 mA
0-2000 700 50