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13
ACB (Auxiliary Control Board) Interface —
The
ACB interface is a dry contact board that can output up to four
signal controlling devices. Refer to Fig. 15 and 24 for
connecting devices to the ACB interface board
Fig. 24 —ACB Interface
START-UP
Pre-Start Check —
Once installation is complete, make
the following pre-start checks:
1. All indoor and outdoor units are properly installed.
2. All piping and insulation is complete.
3. All electrical connections (both power and control) are
properly terminated.
4. All condensate drains are installed correctly.
5. The power supply is the right voltage and frequency.
6. The units are properly grounded in accordance with
current electrical codes.
7. Suction and liquid line service valves are in the open
position.
System Operation Check —
Once the installation
and pre-start checks are complete, perform the following steps:
1. Using the remote controller, select cooling or heating
mode to check the operation of the system.
2. While the system is in operation, check the following on
the indoor unit:
a. Switches or buttons on the remote controller are
easy to push.
b. Indicator light is showing normal operation and no
error is indicated.
c. Swing mode of air louvers is working (if
applicable to unit).
d. Drain pump operation is normal (if applicable).
e. No abnormal vibration or noise.
3. While the system is in operation, check the following on
the outdoor unit:
a. No abnormal vibration or noise is noticed.
b. Condenser fan is in operation.
c. Indicator light is showing normal operation and no
error is indicated.
NOTE:
If the unit is turned off or restarted, there is a time delay
of three minutes for the compressor to start from the time the
power is restored.
MAINTENANCE
EVERY 3 MONTHS:
• Check the air filter condition. Clean or replace if
necessary.
EVERY 6 MONTHS:
Follow the 3-month maintenance schedule. In addition:
• Clean condensate tray with suitable cleaning agent.
• Clean the grille and panel, if applicable.
EVERY 12 MONTHS:
Follow the 6-month maintenance schedule. In addition:
• Be sure all electrical connections are secure.
• Check condensate pump operation.
• Check the heating and cooling action to confirm proper
operation.
INDOOR UNIT ADDRESSING
For proper system operation, each indoor unit must have a
unique address set from 0 to 63. When setting an address by
remote controller, the outdoor units, indoor units, and MDC
must be powered on. If
FE
is displayed on the LED screen or
display board, this unit has no address. After setting all indoor
unit addresses, turn off the power supply to all indoor units to
clear the errors.
Indoor unit addressing can be distributed automatically in the
heat pump system. When dip switch “S6” on the outdoor unit’s
main PCB board is set to 00 (default set in factory), indoor
units are set for auto-addressing. When powering on for the
first time, it takes six minutes or more to finish auto-addressing
each indoor unit. The heat recovery system cannot accomplish
this function at this time.
IMPORTANT: The system can connect 64 indoor units,
with different system addresses. If two indoor units in the
same system have identical addresses, abnormal operation
will occur.
LEGEND
ACB
—
Auxiliary Control Board
FAN
—
Output for fan Operation
CTON
—
Output for Cooling Operation
HTON
—
Output for Heating Operation
AUXH
—
Output for Auxiliary Heat
MAX AMPS
1A
MAX VOLTAGE
24V
CN50
CN51
ACB interface
FAN CTON HTON AUXH
CAUTION
When servicing or repairing this unit, use only factory-
approved service replacement parts. Refer to the rating
plate on the unit for complete unit model number, serial
number, and company address. Any substitution of parts or
controls not approved by the factory will be at the owner’s
risk and may result in equipment damage.
CAUTION
To avoid equipment damage, do not attempt to reuse any
mechanical or electrical controllers that have been wet.
Replace defective controller.