309 B/C – 03/03 A
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Controller
The controller accomplishes its control function with its built-in microprocessor. The two parameters, temperature and
water flow rate, have been factory set before shipment, no need for users to reset them. The controller will display unit
operation status to favor specialized personnel to monitor unit operating condition for maintenance if necessary. When
the system is cut off due to malfunction, the controller will display the corresponding failure code for easy trouble
shooting.
Installation and connection
After removing the terminal box cover, you will find the indoor controller, 20m long indoor connection wire, and 1.5m long
maintenance connection wire. Decide a suitable place for installing the indoor controller, you can either mount it on wall
or embed it in wall. Open the back cover of the indoor controller, plug one end of the indoor connection wire to the CN3
connector located on controller, insert another end to the CN6 connector located on PCB, then assembly the terminal
box cover back, now this work is finished.
Please ensure the 1.5m maintenance connection wire being in good keep for later maintenance by specialized
personnel.
Indoor LCD controller
After switching on power, the indoor controller will display system time, indoor temperature and unit status.
During normal operation, it will display the unit return water temperature.
When failure occurs, it will emit alarm, both audible and visual. Meanwhile show a corresponding error code. Please see
Troubleshooting With Microprocessor
sheet.
a)
On/off
Start an operation
First press [MODE] button, select “cooling” or “heating” mode, then press [ON/OFF] button, the yellow lamp besides the
[ON/OFF] button lights up and the system starts.
Stop an operation
Press the [ON/OFF] button again, the yellow lamp goes off and the system stops.
b)
Indicating lamps on PCB
When the power supply is switched on, the red lamp lights up.
When the system is on operation, the green lamp lights up.
c)
Below are the controllers’ protection functions and features, not its faults.
When restarting the unit after last start or stop, the unit automatically starts compressor and fan after the lapse of
approximately three minutes.
During defrosting cycle, the outdoor fan is stopped.
PCB MAI N
BOARD
TRANSFORMER
RETURN WATER TEMP. SENSOR
HOUR
TIMER
MCH03A
PARAMETER
SET
GROUP
OPERATION
WEEK SET
EXIT
WEEK
CLEAR
UNIT
No.
MODE
SC302A
CONTROLLER
OK
MINUTE
ROOM
TEMP.
ON/OFF
LED1
LED2
SUPPLY WATER TEMP. SENSOR
RETURN AIR TEMP. SENSOR
DEFROSTING TEMP. SENSOR1
DEFROSTING TEMP.
SENSOR2