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B.6.
Buzzer
The unit will beep once when it receives 1 signal.
B.7.
Auto Restart
The system uses non-volatile memory to save the present operation parameters when system is turned
off or in case of system failure or cessation of power supply. Operation parameters are mode, set
temperature, louver’s position, and the fan speed. When power supply resumes or the system is
switched on again, the same operations as previously set will function.
B.8.
On/Off Switch
a)
This is a TACT switch to select Cool→Heat→Off operation mode.
b)
In COOL mode, the set temperature of the system is 24ºC with auto fan speed. There are no timer and
sleep modes.
c)
In HEAT mode, the set temperature of the system is 24ºC with auto fan speed. There are no timer and
sleep modes.
d)
Master unit that does not use a wall pad will globally broadcast.
Note: When button pressing is effective, the master unit buzzer will beep twice and the slave unit will
beep once.
B.9.
Electric Heater Safety Switch
•
Before the electrical heater is turned on, the EH safety switch must be closed and EH is opened for 3
minutes and EC motor RPM must be more than Modbus 300020 setting.
•
When electrical heater is ON, electrical heater safety switch is opened for ≥ 1 second or EC motor
RPM is lower than Modbus 300020 setting, EH will be turned off immediately and report an error
and fan speed is changed to high speed.
•
Once the contact is re
turned to the closed ≥ 180 seconds and EC motor RPM is more than 300020
setting, reset the error and the heater will start again.
•
When the EH safety switch is opened ≥ 3 times within 60 minutes the heater is not allowed to start
anymore.
•
Turn off the unit to reset the fault, provided that the switch has returned to the closed position.
B.10.
Low Temperature Protection of Indoor Coil in Winter
This is frost protection when the unit is off to prevent water from freezing in the coil.
If a 2-pipe system is in Standby Mode, when Tr
≦
2 ºC for 2 minutes, MTV1 is turned on. AUX2 is on. DA1
is 5VDC. If Ti1 < 5ºC for 2 minutes, EH (if present) is switched on. Indoor fan is turned on at low speed. If
Tr
≧
5ºC for 2 minutes, MTV2 is turned off. AUX2 is off. DA1 is 0VDC. Electric Heater is turned off. Indoor
fan is switched off.
If a 4-pipe system (or 2-pipe unit with 6-way valve) is in Standby Mode, when Tr
≦
2 ºC for 2 minutes,
MTV2 is turned on. AUX2 is on. DA2 is 5VDC. (DA1 is 8VDC if using 6-way valve) If Ti1 < 5ºC for 2 minutes
EH (if present) is switched on. Indoor fan is turned on at low speed. If Tr
≧
5ºC for 2 minutes, MTV2 is
turned off. AUX2 is off. DA2 is 0VDC. (DA1 is 5VDC if using 6-way valve) Electric Heater is turned off. Indoor
fan is switched off.
2019-IOM-SWC-V-EC-I-001
