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20
Specifications subject to change without notice. IM-40MBAA-01
Fig. 64 — Cooling and Heating Units Adopt Electric
Heating Device
Fig. 65 — 24V Thermostat Wiring Diagram
Step 10 - Setting Static Pressure and Airflow
The indoor fan coil units can be programmed to have different static
pressures settings or airflows; the factory default setting is SP1.
Follow the next steps to set the static pressure or
Automatic Airflow
using the Wireless Remote Controller according to the installation
conditions.
• The external static pressure can be manually changed to the fan
curves SP2, SP3, SP4.
• Choose the Automatic Airflow
“AF”
adjustment function to
automatically identify the static pressure and regulate the airflow
amount.
Follow these instructions to configure:
1. Ensure the test run is done with a dry coil. If the coil is not dry, run
the unit for 2 hours in the
FAN ONLY
mode to dry the coil.
2. Check that both the power supply wiring and the duct installation
have been completed. Check that dampers are properly positioned.
Check that the air filter is properly attached to the air return side
passage of the unit.
3. If there is more than one air inlet and/or outlet, adjust the dampers
so that the airflow rate of each air inlet and outlet conforms to the
designed airflow rate. Ensure the unit is in
FAN ONLY
mode.
Press and set the
Airflow Adjustment “AF”
on the remote
controller to adjust the airflow rate from
H
to
L
. Turn the indoor
unit
OFF
with the Wired Controller.
4. To set the parameters for airflow adjustment. When the system is
OFF
, perform the following steps:
a.
Press and hold
COPY
for approximately 4 seconds
b.
Press “
+
” or “
-
” to scroll through the menu and make a
selection, either
SP
or
AF
.
NOTE:
T1, T2, T2b, T3, T4 are sub-menus for thermistors.
DO
NOT
select to set the external static pressure.
Fig. 66 — Wired Controller Menu Selection
1. If setting the external static pressure manually, select
SP
and press
CONFIRM
. Select the
SP
number (SP1, SP2, SP3, SP4). Power
down the unit to lock in the selection.
2. If choosing the
AUTOMATIC AIRFLOW ADJUSTMENT
function, select
AF
and press
CONFIRM
. The system starts the
fan for the airflow automatic adjustment. The
ON
indicator flashes
when the fan runs during the
AUTOMATIC AIRFLOW
ADJUSTMENT
. After 3 to 6 minutes, the system stops operating
once the
AUTOMATIC AIRFLOW ADJUSTMENT
is
complete.
Fig. 67 — Automatic Airflow ON signal
WHEN USING THE 24V INTERFACE BUILT-IN*
The wireless remote controller is required to setup the static
pressure of the indoor ducted units.
NOTE:
When a system is using the 24V interface, the indoor unit’s
fan speed defaults to
AUTO
with the indoor unit’s default logic.
INDOOR UNIT OUTPUT WITH 24VAC 1.5A
INDOOR UNIT
THERMOSTAT
BROWN
RED
YELLOW
GREEN
BLUE
White
Aux
Aux
CN15
R C
CN18
CN19
G1 G2 G3 Y W G
2
4
V R
2
4
V C
Cool
Heat
Auto_Fan
Aux/Dry
CN22
24V THERMOSTAT
“ON”
is running during the
AUTOMATIC AIRFLOW ADJUSTMENT
Do not use the
AUTOMATIC AIRFLOW ADJUSTMENT
with
the remote control if using booster fans, an outdoor air processing
unit, or a HRV via duct.
If the ductwork or static pressure have been changed, reset the
AUTOMATIC AIRFLOW ADJUSTMENT
.
CAUTION