Specifications

Manual 2100-549L
Page 34 of 59
I-TEC COMMERCIAL ROOM
VENTILATOR SYSTEM
GENERAL DESCRIPTION
The I-TEC Commercial Room Ventilator (CRV) is
designed to be used with all Bard I-TEC models. The
only intent of this device is to provide the required
ventilation by delivering fresh air to meet I.A.Q. (Indoor
Air Quality) requirements. In the installed application,
this system also includes exhaust provisions which
are balanced with the intake air to maintain building
pressurization requirements of ASHRAE 62.1
Standard.
Ventilation is accomplished with (2) 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 I-TEC CRV is also provided with filters to reduce
the required service needed and to further improve
the I.A.Q. 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
The I-TEC CRV comes wired from the factory set to
375 CFM of ventilation. Care must be taken when
deciding how to control the operation of the ventilator.
When designing the control circuit for the ventilator,
the following requirements must be met.
1. The indoor blower must be run whenever the I-TEC
CRV is run.
2. Select and configure the correct CFM ventilation
level that the I-TEC CRV needs to operate and
configure the system to this level following later
instructions within this section. Over ventilating
serves no useful purpose and significantly affects
the overall efficiency of the heat pump system.
System operating costs would also increase.
3. Run the I-TEC CRV only during periods when
the conditioned space is occupied. Running the
ventilation during unoccupied periods wastes
energy, decreases the expected life of the CRV,
and can result in large moisture buildup in the
structure. Running the CRV when the structure
is unoccupied allows moisture to build up in the
structure because there is little or no cooling load.
Thus, the air conditioner is not running enough to
remove the excess moisture being brought in. Use
a control system that in some way can control the
system based upon occupancy.
RECOMMENDED CONTROL
SEQUENCES
Several possible scenarios are listed below:
1. Use a programmable electronic thermostat with
auxiliary terminal to control the CRV based on
daily programmed occupance periods. Bard
markets and recommends Bard Part #8403-060
programmable electronic thermostat.
2. Use Bard CompleteStat™ that incorporates
temperature, humidity and occupancy control
with learning capability into a single device. No
programming required.
3. Use a DDC control system to control the CRV
based upon a room occupancy schedule to control
the CRV.
4. Tie the operation of the CRV into the light switch.
The lights in a room are usually on only when
occupied.
5. Use a manual timer that the occupants turn to
energize the CRV for a specific number of hours.
6. Use a programmable mechanical timer to energize
the CRV and indoor blower during occupied periods
of the day.
NOTE: The ventilation package comes with a blower
interlock function, but is disabled when it is shipped
from the factory in case you do not utilize a thermostat
with an occupancy output, or a occupancy sensor
and must tie “A” terminal to “G” terminal to drive the
ventilation package. If you do have a thermostat or
control that does drive occupancy output, you will need
to remove the tape from the orange wire located in the
low voltage terminal box, and connect it to the “G”
terminal to activate this function. (See Figures 13-19.)
SETTING THE VENTILATION CFM
LEVELS
The I-TEC CRV has four pre-set levels of ventilation
CFM available. These are 300, 375, 450 and 525
CFM of ventilation air. The I-TEC CRV is shipped from
the factory set on the 375 CFM ventilation level. To
change between these four different levels of provided
ventilation CFM, first refer to Figure 21 to look up the
corresponding CFM needed for the intake and exhaust
blowers to meet the design criteria and determine
which “speed/wire color” is needed. Then, perform the
following steps.
Operating the I-TEC CRV during unoccupied periods can
result in a build up of excess moisture in the structure.