Low Voltage Connections; General - Bard Q24A2DA Installation Instructions Manual

The Climate Control Option J is an electronic,
programmable thermostat with humidity control and is
BACnet compatible. The thermostat can be set in the
heat, cool or automatic mode. When the thermostat is
set in the heat mode, it can heat only to maintain the
temperature set on the thermostat. When the thermostat
is set in the cool mode, it can cool only to maintain the
temperature set on the thermostat. When the thermostat
is set in the automatic mode, the thermostat can change
automatically to the heat or cool modes to maintain
the temperature set on the thermostat. This thermostat
supports BACnet IP, MS/TP and Ethernet protocols.
The Climate Control Option K is an electronic,
programmable thermostat with humidity and CO
and is BACnet compatible. The thermostat can be set in
the heat, cool or automatic mode. When the thermostat
is set in the heat mode, it can heat only to maintain the
temperature set on the thermostat. When the thermostat
is set in the cool mode, it can cool only to maintain the
temperature set on the thermostat. When the thermostat
is set in the automatic mode, the thermostat can change
automatically to the heat or cool modes to maintain the
temperature set on the thermostat.
The CO controller will energize the vent option and the
2
ID blower when the room CO
Default CO set point is 1000 ppm. See Figure 23.
2
NOTE: On option X (a field provided means to
control ventilation) must be used if any of the
motorized ventilation options are installed.
NOTE: Thermostats are shipped in the bottom of
the unit and must be mounted to the factory
mounted subbase at time of installation.

GENERAL

This unit is equipped with a variable speed ECM
motor. The motor is designed to maintain rated airflow
up to the maximum static allowed. It is important
that the blower motor plugs are not plugged in or
unplugged while the power is on. Failure to remove
power prior to unplugging or plugging in the motor
could result in motor failure.
control
2
levels rise over set level.
2
CAUTION
Do not plug in or unplug blower motor
connectors while the power is on.
Failure to do so may result in motor failure.

LOW VOLTAGE CONNECTIONS

FOR DDC CONTROL
Fan Only
Cooling Mode
1st Stage Heating
2nd State Heating
(if employed)
Ventilation
Dehumidification
LOW VOLTAGE CONNECTIONS
These units use a grounded 24 volt AC low voltage
circuit.
The "R" terminal is the hot terminal and the "C"
terminal is grounded.
"G" terminal or pin 6 of P2 is the fan input. If the
climate control option is abandoned and connections
are made directly to P2 pin 6 of P2 must be energized
for proper operation.
"Y1" terminal or pin 7 of P2 is the compressor input.
"W1" terminal or pin 8 of P2 is the fist stage heat.
"R" terminal or pin 10 of P2 is 24 VAC hot.
"C" terminal or pin 11 of P2 is 24 VAC grounded.
Terminal "1" or pin 4 of P2 is the dehumidification
circuit.
Terminal "2" or pin 12 of P2 is the dehumidification
circuit. A contact must connect terminals 1 and 2.
"W2" terminal or pin 9 of P2 is second stage heat (if
equipped). If the unit is equipped with an optional hot
water coil plenum box or electric heat these will be
energized by this terminal.
"F" terminal of pin 5 of P2 is the ventilation input.
This terminal energizes any factory installed ventilation
option.
NOTE: For total and proper control using DDC, a total
of 6 controlled outputs are required (5 if no
ventilation system is installed).
Energize G
Energize Y1, G
Energize G, W1
Energize G, W2
Energize G, F
Energize contact
between 1 and 2
Manual 2100-602A
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