Manual 2100-549Q
Page
38 of 69
GENERAL DESCRIPTION
The I-TEC Combination Commercial Room Ventilator
(CRV) and Dry Bulb Economizer is designed to be used
with all Bard I-TEC models. This ventilation package
and its control provides two roles:
• It will provide the required ventilation by delivering
fresh air to meet IAQ (Indoor Air Quality)
requirements through CRV portion of the device.
• It will provide up to 525 CFM of free outdoor
cooling CFM when the outdoor ambient
I-TEC COMBINATION CRV AND
ECONOMIZER VENTILATION SYSTEM (VENT CODE "N")
temperature is below the outdoor thermostat
setpoint.
Ventilation is accomplished with two blower/
motor assemblies for maximum ventilation at low
sound levels. The intake and exhaust blowers are
programmed independently and are balanced to
maintain a slight positive pressurization in accordance
to ASHRAE 62.1 Standard.
The ventilation package is also provided with filters
to reduce the required service needed and to further
improve the IAQ. The exhaust air blowers are protected
by disposable filters and the intake air blowers are
protected by washable filters. Both are accessible
without the need for tools.
CONTROL WIRING
Refer to Low Voltage Connection (Figure 19).
Reference Figure 23 for Control Sequence of
Operation.
7
NC
7
D
R2
6
Y2
NO
R3
COM
NO
3
R4
ECON VENT SPEED
YO
A
FACTORY WIRE
A
R1
D
6
G
R
Y2
8
Y1
C
Y1
R4
R2
R1
R3
4
COM
R2
7
1
R2
5
8
COM
R2
R1 = DEHUM RELAY
R2 = HIGH AMBIENT RELAY
R3 = FULL LOAD RELAY
R4 = BLOWER INTERLOCK RELAY
FIELD WIRE
CRV VENT SPEED
MIS-3272
UNIT LOW
VOLTAGE
TERMINAL
STRIP
THERMOSTAT
SIGNALS
Operating the I-TEC CRV during unoccupied
periods can result in a build up of excess
moisture in the structure.
FIGURE 23
Economizer Control Circuit
