Nortek B6BM Series, Руководство по установке

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12
Air circulation
Running the Blower Continuously
Set the thermostat’s system mode to oFF and the thermostat’s
fan mode to oN. The blower motor should run continuously.
Check for air delivery at the register(s). Ensure that there are
no obstructions at the registers or in the ducts.
Selecting Continuous Low Speed Fan Operation
(Standard Blower)
The air handler is equipped with an option of continuous low
speed fan operation. When
G is energized without Y/Y2, the
air handler will operate using the cooling speed. With
G &
Y/Y2 or Y/Y2 energized, the air handler will operate in the
selected cooling speed (including 40 sec blower-off delay).
Turning the Blower Off
Set thermostat’s fan mode to Auto, the blower will shut
down immediately.
System Cooling
1. Set the thermostat’s system mode to
cooL and fan mode
to
Auto. Lower the thermostat’s temperature mode below
room temperature and observe that the blower energizes.
Check the air being discharged at the register is cooler
than room temperature. Verify unit refrigerant pressures
are in order. Blower should be turning in direction indicated
by arrow.
NotE: DO NOT alter unit wiring. Listen for any unusual
noises. Locate the source and correct as needed.
2. Allow the unit to run for several minutes and then set the
thermostat’s temperature above room temperature. Verify
the blower cycles off with the thermostat.
System Heating
1. Set the thermostat’s system mode to HEAt and the fan
mode to Auto. Increase the thermostat’s temperature
above room temperature and observe that the blower
energizes. Check the air being discharged at the register
is warmer than room temperature.
2. Allow the unit to run for several minutes and then set the
thermostat’s temperature below room temperature. Verify
the blower cycles off with the thermostat.
Selecting Minimum Electric Heat Airflow
The minimum electric heat airflow setting controls the
minimum air flow that will be produced whenever electric
heater kits are used. When the electric heater kit is energized
along with a heat pump, the airflow may be higher depending
on the basic cooling/heat-pump airflow setting. The minimum
electric heat airflow is selected by the red blower wire on
3-speed models or setting switches 1, 2, 3, & 4 on B6EM
models. B6VM models automatically set the heating speed
based on the amount of installed heat. The A/B switch must
be set appropriately for the unit cabinet size. For C-sized
cabinets, the A/B switch can be set in either position. The
remaining 3 HEAT switches have no function. Switch settings
are listed in Table 7, (page 18) or Table 10, (page 20) .
NotES:
• For B6EM Models, the minimum electric heat airflow setting
may be set higher, but must never be set lower than the
setting shown in Table 8, (page 19) .
• Variable speed motor control boards do not support non-
electric heat because the heating air flow cannot be set
independently.
Blower configurations
Determining Nominal System Capacity
To select the appropriate airflows for the air handler, the
nominal system capacity must be known. The nominal system
capacity is always the nominal capacity of the outdoor unit.
However, in some situations the nominal system capacity may
not be the same as the nominal capacity of the air handler.
Always refer to the nominal capacity of the outdoor unit to
determine the nominal system capacity. Use Table 9, (page
19) as a guide for acceptable airflow CFM (dependent on air
handler cabinet size and nominal capacity of the outdoor unit).
NotE: The CFM values listed in
Table 10, (page 20) are
not dependent on duct static pressure. The VSHE motor
automatically compensates for changes in duct static pressure
(within the limits of the motor).
3-Speed Units
The blower speed is preset at the factory for operation at the
same speed for heating and cooling, by using the jumping
terminal on the blower motor and connecting it to the desired
speed with both the red and black wires connected to the
jumping terminal. NotE: The control board is programmed
with a 40 second off delay in the cooling mode for optimum
system performance and efficiency.
cAutIoN:
to avoid personal injury or property damage,
make sure the motor leads do not come into
contact with any uninsulated metal components
of the unit.
For optimum system performance and comfort, it may be
necessary to change the factory set speed. See Table 6,
(page 17) for airflow data. To change the blower speed:
1. Disconnect all electrical power to the unit and remove the
upper door.
2. Remove the black and red wires from the blower motor
jumping terminal. Discard the blower motor jumping
terminal.
3. Connect the heating speed wire (red) and the cooling
speed wire (black) to the desired blower speed marked
on the terminal block of the blower motor.
• Terminal 4 = Hi speed
• Terminal 5 = Med speed
• Terminal 6 = Low speed
4. Replace the upper door and secure it to the unit.
5. Restore power to the unit.
High Efficiency Units (Variable & Fixed Speed)
IMPoRtANt! This air handler has been designed to give the
installer maximum flexibility to optimize system performance,
efficiency, and comfort. Because there are so many different
ways to set up the air handler it is important to read and
follow these directions carefully.
B6EM & B6VM air handlers use high efficiency circulating air
motors that come in two variations and both are controlled
differently. The variable speed motor control board ( Figure
18 ) controls the airflow at a constant CFM when paired with
a separate control board. The fixed speed unit has a single
integrated control board ( Figure 17 (page 27) ) that controls
the torque of the motor.
Before operation, the air handler must be configured to
match the unit with the system, system options, and climatic
conditions. During normal operation, the motor will gradually