Bard CRV-V2-A Commercial Room Ventilator Instruction Manual
- June 14, 2024
- Bard
Table of Contents
Bard CRV-V2-A Commercial Room Ventilator
General Information
Commercial Room Ventilator Features
- One piece construction – easy to install with no mechanical linkage adjustment required.
- Exhaust air damper – built in with positive closed position. Provides exhaust air capability to prevent pressurization of tight buildings.
- Actuator motor – 24 volt, power open, spring return with built in torque limiting switch.
Commercial Room Ventilator Model Nomenclature
Unpacking
Upon receipt of the equipment be sure to compare the model number found on the
shipping label with the accessory identiÿcation information on the ordering
and shipping document to verify that the correct accessory has been shipped.
Inspect the carton housing of each ventilator as it is received, and before
signing the freight bill, verify that all items have been received and that
there is no visible damage. Note any shortages or damage on all copies of the
freight bill. The receiving party must contact the last carrier immediately,
preferably in writing, requesting inspection by the carrier’s agent. Concealed
damage not discovered until after loading must be reported to the carrier
within 15 days of its receipt.
Field-Supplied Tools Needed
- Appropriate personal protection equipment, including gloves and safety glasses
- 5/16″ nut driver
- Phillips head screwdriver
- Small flat head screwdriver for securing wire in terminal blocks
- Electrical tools
- Multimeter
General
The ventilator should only be installed by a trained heating and air
conditioning technician. These instructions serve as a guide to the technician
installing the ventilator package. They are not intended as a step-by-step
procedure with which the mechanically inclined owner can install the package.
The ventilator housing is shipped in one carton which contains the electrical
harness, miscellaneous hardware and installation instructions.
Description
The CRV-V ventilator is designed to be used with
the speciÿc models with “letter” revision codes as designated on the front
page of this installation instructions manual.
The built-in commercial room ventilator with modulating blade position is
internally mounted behind the service door and allows outside ventilation air,
up to 50% of the total air°ow rating of the unit. It includes a built-in
exhaust air damper for room pressurization relief. Blade seals allow for
minimal blade leakage.
A ventilation control board allows multiple blade settings to adjust intake
air°ow. By setting multiple blade positions, pre-purge, occupied, and
unoccupied air°ow amounts are possible with capable thermostats and
controllers. The CRV-V also allows for 0-10V or
4-20ma input for modulating ventilation control based on CO2 levels. Complies
with ANSI/ASHRAE Standard 62.1 “Ventilation for Acceptable Indoor Air Quality”
and other state and local ventilation codes that require outdoor air intake
but not economizer operation.
Models
When installed in the models listed on the front page, the CRV-V provides
built-in exhaust provisions. When the damper blade opens to bring fresh air
in, the damper also opens an exhaust relief. The exhaust air will °ow into the
condenser section of the unit. The condenser fan will help draw exhaust air
out when it is operating with compressor in cooling or heat pump mode.
INSTALLATION OF FIELD-INSTALLED CRV-V*
Basic Installation
WARNING
Electrical shock hazard.
Disconnect remote electrical power supply or supplies before servicing.
Failure to do so could result in electric shock or death.
Preparing Unit for CRV-V Installation
-
Disconnect power to unit.
-
Unpack the CRV-V assembly, which includes the integral controls and electrical harness, body panels, miscellaneous hardware and installation instructions.
-
From existing wall mount unit, remove and save (or discard) as directed:
- Blower access panel (save)
- Vent option panel (discard)
- Filter access panel (save)
- Filter (save)
- Outer and inner control panel doors (save)
- Filter brackets (discard, if applicable)
- Exhaust cover plate (discard)
-
Install new condenser exhaust plate with screen over opening into condenser section.
-
Verify what type of ÿlter racks are in the unit. The unit may include either a ÿlter partition and tray assembly, or two separate ÿlter brackets.
If the unit contains a partition and tray assembly, this may be left as-is for the ventilator installation. If the unit contains two separate ÿlter brackets, remove ÿlter brackets. Two types of ÿlter brackets have been used with these wall-mount units. If the ÿlter brackets are mounted °at, they can be used with the commercial room ventilator (CRV). If the brackets are set at a 30° angle, they must be removed, discarded and ÿll plates added. The circuit breaker offset plate must be loosened and moved slightly to gain access to several of the screws holding the ÿlter brackets in place. Tighten the screws holding control panel after the ÿlter brackets have been removed.
If ÿlter brackets were removed in Step 5, proceed to Step 6. If the brackets were not removed, proceed to Commercial Room Ventilator (CRV) No Hood Installation. -
Install ÿlter bracket ÿll plate (if applicable) as shown in Figure 3 on page 6 (for units with two filter brackets) or Figure 4 on page 7 (for units with a ÿlter partition and tray assembly).
-
Install provided ÿlter brackets on CRV-V assembly.
Commercial Room Ventilator (CRV) No Hood Installation
- Insert CRV into opening in the wall mount unit between the filter rack and the condenser section, being careful not to tear the unit insulation. Fully seat CRV assembly to rear of the cavity. Slide the CRV toward the control panel so that it lines up with the return air opening in the rear of the wall mount unit. For installation in left control panel units,
- Insert and lock in the 12-pin plug end of the wire assembly into the front side of the unit’s control panel.
- Replace the air ÿlter if it was removed (air°ow direction is up).
- The next step involves installing the unit’s filter door and putting the mist eliminator filter into place.
- With the lower vent option door removed, locate the control board. Then, make all the required thermostat connections per the applicable connection diagram found on pages 14 – 17, and restore power to the unit.
- Make any necessary changes required to the potentiometers to achieve the minimum continuous air°ow and total air°ow desired. Refer to Blade Adjustment for Desired Ventilation Air on page 19 for more information on adjusting the potentiometers.
- Replace the vent option panel with the door that is provided in the CRV kit. Attach using the four (4) provided screws .
CO2 Control
For CO2-based control, order CO2 sensor/controller separately (Bard part
8403-096) and add to the wall and run additional optional wires as shown in
the wiring diagrams.
The CO2 controller must also be reconÿgured from the standard
default settings as shipped from the factory. 
Control System Notes
This ventilation package is capable of being set to meet the current ASHRAE
speciÿcations for minimum occupied air°ow rates, with extended capability to
meet demand ventilation requirements.
Two Switch Application
Energizing the A terminal in the low voltage connection box during occupied
conditions will allow the prepurge and minimum occupied air°ow rates to be set
to meet ASHRAE requirements. This can be accomplished by adjusting the PP and
OCC potentiometers on the CRV control board by aligning the damper position
per the charts.
Blade Adjustment for Desired Ventilation Air
The amount of ventilation air supplied by the commercial room ventilator is dependent on four factors.
- Return air duct static pressure drop.
- Supply air duct static pressure drop.
- Indoor blower motor speed.
- Damper blade open position setting.
Refer to the appropriate graph to determine the blade setting necessary to
achieve the ventilation air required for each operating mode.
All potentiometers are set in the closed position from the factory.
Turning potentiometers counter clockwise will close the blade; clockwise will
open the blade.
“V” Option CRV Sequence of Operation
The “V” Ventilation option includes a control board with blade positioning
potentiometers along with an input for a 2-10V input signal .
Adjustable potentiometers:
“PP” Potentiometer setting: This potentiometer can be used to adjust the
blade setting for outdoor air intake during a pre-purge cycle. The pre-purge
cycle time is based on the setting of the pre-purge timer.
“OCC” Potentiometer setting: This potentiometer can be used to adjust the
blade setting for outdoor air intake when the “A” terminal is energized on the
low voltage terminal strip indicating occupancy.
“Y1” Potentiometer setting: This potentiometer can be used to adjust the
blade setting for outdoor air intake when the “Y1” terminal is energized on
the low voltage terminal strip indicating 1st stage cooling or Balanced
Climate operation. When energized, it overrides the
“OCC” potentiometer setting.
“Y2” Potentiometer setting: This potentiometer can be used to adjust the
blade setting for outdoor air intake when the “Y2” terminal is energized on
the low voltage terminal strip indicating 2nd stage cooling operation. When
energized, it overrides the “OCC” and “Y1” potentiometer settings.
Pre-Purge Feature
Pre-purge is used to ventilate a specified CFM amount before occupants enter
the room or structure. The control board has a built-in pre-purge timer that
can be set to 30, 60 and 90 minute intervals by moving the jumper. This timer
will start when the jumper is installed and the A terminal is energized on the
low voltage terminal strip. Blade adjustment can be made on the PP
potentiometer. Once the timer has timed out, the board will default to the
occupied setting and this blade position can
be adjusted on the OCC potentiometer. If the timer is set to 0 (off—shipped
position), the occupied setting is instantaneous and the pre-purge setting
(PP) is no longer in the sequence.
Occupied Setting
Occupied is used to ventilate a specified CFM amount when occupants enter the
room or structure. The control board will energize the occupied setting after
the pre-purge cycle, or if pre-purge is disabled immediately when the A
terminal is energized on the low voltage strip. Blade adjustment can be made
on the OCC potentiometer.
Y1 Setting
Y1 is used to ventilate a specified CFM amount when Y1 cooling is energized.
If Balanced Climate operation is used, the Y1 setting should be set to a blade
setting that will allow additional outdoor intake air. The control board will
energize the Y1 setting when Y1 is energized on the low voltage strip. Blade
adjustment can be made on the Y1 potentiometer. This potentiometer setting
overrides the OCC occupied setting.
Y2 Setting
Y2 is used to ventilate a specified CFM amount when Y2 cooling is energized.
The blade setting for the Y2 potentiometer must be set to match the occupied
setting (OCC potentiometer) in order to bring in the same amount of outdoor
air when non-Balanced Climate cooling occurs. The control board will energize
the Y2 setting when Y2 is energized on the low voltage strip. Blade adjustment
can be made on the Y2 potentiometer. This potentiometer setting overrides the
OCC occupied and the Y1 setting.
2-10V Operation
A CO2 sensor or other device sending a 2-10V signal can be used to control the
damper motor.
Two control methods are available to control the damper motor:
- Method 1: The control board will accept a 2- 10VDC signal with a resistive load greater than 5000 ohms. Bard CO2 sensor part #8403-056 can be used when the 2-10V output is connected to terminal 4 on the unit low voltage terminal strip. The occupied OCC potentiometer setting must be set to the off position for total modulation. The OCC potentiometer can be used to maintain a minimum blade position when A is energized.
- Method 2: The damper motor will accept a 2- 10VDC signal with a resistive load less than 5000 ohms. This method involves bypassing the control board and powering the motor directly from the device providing the 2-10VDC modulating signal. The gray wire from pin 4 on the 12 pin connector (2-10V IN on control board) must be spliced with the white wire ran to the damper motor (2-10V OUT on control board).
During 2-10VDC operation with A energized and pre-purge timed operation active, DC voltage signaling occupancy from a source such as a CO2 sensor will increase ventilation amounts as needed.
Unit Operation| Occ. Signal| Low Voltage 24VAC|
Speed Taps| Fan Speed| Comp. Oper.| Damper
Pot.
---|---|---|---|---|---|---
G| Y1| Y2| W1| W2| A| D| 1| 2|
3-4-5 1
Fan Only| Yes| X| | | | | X| | X| | | Vent| Off| PP/OCC
Fan Only| No| X| | | | | | | X| | | Vent| Off| Closed
BC Cooling2| Yes| | X| | | | X| | X| X| | B Climate| On| Y1
BC Cooling2| No| | X| | | | | | X| X| | B Climate| On| Closed
Full Load Cool| Yes| | X| X| | | X| | X| X| X| Lo/Med/Hi| On| Y2
Full Load Cool| No| | X| X| | | | | X| X| X| Lo/Med/Hi| On| Closed
1st Stage Heat| Yes| | | | X| | X| | | | X| Lo/Med/Hi| Off| Y2
1st Stage Heat| No| | | | X| | | | | | X| Lo/Med/Hi| Off| Closed
2nd Stage Heat| Yes| | | | X| X| X| | | | X| Lo/Med/Hi| Off| Y2
2nd Stage Heat| No| | | | X| X| | | | | X| Lo/Med/Hi| Off| Closed
Dehumidify3| Yes| | | | | | X| X| X| X| | B Climate| On| Y1
Dehumidify3| No| | | | | | | X| X| X| | B Climate| On| Closed
BC and B Climate − Balanced Climate
- Fan speed is selectable through the blower speed control terminal block. LO (default), MED or HI speeds can be used.
- Y1 and Y2 jumper must be removed on low voltage terminal block connections and 2 stage thermostat must be utilized.
- Dehumidiÿcation operation is disabled when a call for heating or cooling occurs. Unit runs at Balanced Climate speed during dehumidiÿcation operation.
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