Nortek B6BM Series, Руководство по установке

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See Figure 15 (page 26) or Figure 16 (page 26) and
Table 13A, (page 22) , Table 13B, (page 23) , & Table
13C, (page 24) for control board modes and actions.
twinning
These instructions are to be used when connecting two B5 or
B6 air handlers (2-5 ton models) to a common single stage
A/C condensing unit or heat pump. Twinning is possible for
B5 units with PSC or X-13 motors and B6 units with PSC
or fixed speed (FSHE) motors. Twinning is not possible for
units with variable (VSHE) speed motors. All low voltage
wiring instructions, cautions, and warnings accompanying
the air handler remain applicable, except for:
Line & Low Voltage Connections
a. The line voltage connections for both air handlers must
be the same phase and on the same leg of power.
b. When matched with an S3BM or an S3BW series AC
outdoor unit, both air handler’s 24V transformers must
be removed from the control circuit by removing and
discarding the RED wire located on the transformer’s
secondary. These outdoor units come standard with 24V
power supply sufficient for powering both air handlers.
c. Low voltage wiring should be connected as shown in
Figure 14 (page 25) .
d. Wire all other low voltage thermostat terminals to
both air handlers as shown in Figure 13 (page 25) .
NotE: If there is any other air moving device in the
duct work, consult the factory for a resolution.
Heater Kits
When electric heat packages with circuit breakers are field-
installed, the circuit breaker may be used as a disconnecting
means in most applications. Reference the NEC and local
codes for disconnect requirements.
If a heater kit is installed:
B6BM, B6EM, & B6VM air handlers are shipped from the
factory without an electric heater kit installed. If electric heat
is desired, a heater kit may be purchased separately and
field installed. Determine the correct size heater kit for your
unit by referring to the list below or the units rating label.
A-Size Cabinet ............................................... 15Kw max
B-Size Cabinet ............................................... 20Kw max
C-Size Cabinet .............................................. 30Kw max
1. Connect the 2 wire plug of the air handler to the mating 2
wire plug of the heater kit.
2. Connect the line voltage leads to the circuit breaker or
terminal block provided.
3. Connect the heater kit plug with the mating receptacle on
the air handler control board.
If a heater kit is not installed:
1. Remove the 2 wire plug of the air handler by cutting the
wires and discarding the plug.
2. Strip the ends of the 2 air handler wires and connect to
the line-voltage leads with the 2 wire nuts provided.
Humidifier
The unit has an output to power a humidifier when the blower
is running. This output is rated to 1.0 amp at 208/240V.
Dehumidification options
The motor control board has a DHuM or D connection that
allows the system to increase the amount of humidity that
is removed from the circulating air. See Figure 17 & Figure
18 (page 27) This is accomplished by reducing the CFM
and allowing the cooling coil to become colder. This will only
occur when there is a call for cooling. There are many ways
that this can be electrically wired.
1. If the room thermostat incorporates a humidity sensor and
DHuM output, connect the DHuM on the thermostat to
the
D terminal on the motor control board. See
Figure 10 .
2. If using a separate humidistat, connect the
DHuM & R
terminals on the humidistat to the D & R terminals on
the motor control board of the air handler. In this option,
the DHuM output of the humidistat must be set so it is
only closed when there is a call for dehumidification.
3. If a humidistat is not available, it is an acceptable option
to connect the
R & D terminals on the motor control board
together with a field supplied wire. This option causes
the blower to run at a reduced CFM for 10 minutes after
a call for cooling. NotE: If outdoor unit is a heat pump,
connect the
o terminal to the D terminal.
Electronic Air cleaner (EAc)
The unit has an output to power an electronic air cleaner
when the blower is running. This output is rated to 1.0 amp
at 208/240V. See Figure 16 (page 26) and Figure 17
(page 27) .
StARtuP & ADjuStMENtS
Before You Start the unit
Prior to start-up, complete the following inspections:
√
Verify the unit is level and properly located with adequate
clearances for servicing the unit as shown in Table 1,
(page 4) .
√
Check condensate drain line(s) for proper drainage.
√
Verify the surrounding area and top of the unit is free from
obstructions and debris.
√
Check all duct connections. Make sure the duct work is
adequately sealed to prevent air leakage.
√
Check all coil connections for leaks.
√
Verify that the line voltage power leads are securely
connected and the unit is properly grounded. Make sure
all doors are installed before restoring power to the unit
√
Verify the thermostat is wired correctly. Make sure all low
voltage wires are securely connected.
√
Verify the power supply branch circuit overcurrent protection
is sized properly.
√
Verify filter is properly and securely installed.
IMPoRtANt: Before starting the unit, install the initial
charge on units that are factory shipped with a nitrogen
holding charge:
1. Read all installation instructions first.
2. Purge the nitrogen holding charge.
3. Evacuate the unit to 350 - 500 microns.
4. Allow the unit to remain under vacuum for at least 30
minutes.
5. Weigh in the proper amount of new (or reclaimed)
refrigerant. Refer to the air conditioner or heat pump
installation manual for the proper type and quantity of
refrigerant.
DHUM
R
R
DHUM
HUMIDISTAT
MOTOR
CONTROL BOARD
Figure 10.
DHuM Wiring configuration