Gree GRH120DB-K6NA1A Service Manual page 21

If the time is set within 10 hours, the timing interval is 0.5h; If the time is set more than 10 hours, the timing interval is 1h.
3.4 Memory Function
The system will remember the settings when power is interrupted. The unit will automatically restart in the last setting used after the
power is restored. If the air conditioner is on when power is interrupted, it takes 3 minutes for the compressor to restart after the power
is restored, If the air conditioner is off when power is interrupted, there is no need to wait after power is restored.
3.5 Lights and Dual-8 Nixie Tube
a. When unit is on and under cooling mode, the Cooling indicator will turn on while tube shows the set temperature. Temperature can be
set;
b. Under heating mode, the Heating indicator will turn on while tube shows the set temperature. Temperature can be set.
c. When the power is on but the unit is off, the on/off indicator will turn on, and when unit is turned on, the on/off indicator will turn off.
d. When unit is on and lights of all buttons on the remote controller go off, all set lights (except the LED light ) light and dual 8 nixie tubes
will go off accordingly (except malfunction indicator and filter indicator). When the controller is receiving signals, the main board will
remember the set parameter, which would be displayed after the remote light is turned on.
3.6 Temperature Setting
(1) Temperature can be set by pressing the button +/-. Dual-8 nixie tube will show the temperature while setting.
(2) The tube display can show degree Fahrenheit or degree Celsius. The default temperature reading on the display is degree Celsius.
To change the display to degree Celsius, press the button + and - together and hold for 3 seconds. Repeat the process to change back
to degree Fahrenheit.
3.7 Controls
(1)ON/OFF: Turn air conditioner on and off. When air conditioner is off, press the button to turn it on. When air conditioner is on, press
the button to turn it off;
(2)FAN SPEED: Use to set the fan speed to FANL, FANM or FANH on the unit.
(3)+/-: Use to set temperature and the delay time;
(4)MODE: Use to switch different modes. it can be circulated to COOL,FAN,HEAT,COOL;
(5)WIFI, TIMER and Sleeping mode can only be set by a remote controller.
(6)Auto mode can only be set by a remote controller and displayed on it.
(7) FILTER CHECK: This feature is a reminder of cleaning the air filter(normal maintenance) for more efficient operation. The light will
turn on automatically after the fan works more than 250 hours. If the light is on, turn off and power off the unit, take the air filter out and
clean it, then re-install the air filter, power on and turn on the unit, the light will still be on, press FILTER CHECK button,the light will turn
off.
(8)Light:Turn on or off the control panel display.
(9) LED on the remote controller: As long as the unit is powered regardless of its on or off, press the button once to turn the LED light
on or off. LED light can only be set by a remote controller. If the unit is powered the first time, LED light will turn on in the indoor panel.
3.8 Protection
3.8.1 Temperature sensors' malfunctions detected
(1) Indoor ambient temperature sensor is open/short-circuited: dual-8 nixie tube shows F1;
(2) Indoor tube temperature sensor is open/short-circuited: dual-8 nixie tube shows F2;
(3) Outdoor ambient temperature sensor is open/short-circuited: dual-8 nixie tube shows F3;
(4) Outdoor tube temperature sensor is open/short-circuited: dual-8 nixie tube shows F4;
(5)If different malfunctiuons occur at the same time, error codes will show in a circulated way
3.8.2 Alarm Function of Filter
If the total operating time of the fan reaches 250 hours, the filter indicator will turn on to remind user to do the cleaning.
3.8.3 Refrigrant loss protection' malfunctions detected
If the the unit enters refrigrant loss protection 6 times, the dual-8 nixie tube shows F0.
3.8.4 Compressor overload protection' malfunctions detected
If the the unit enters compressor overload protection 6 times, the dual-8 nixie tube shows H3.
3.8.5 Low voltage protection' malfunctions detected
If controller detects that system voltage lower than the limit value for 30s, the dual-8 nixie tube shows PL.
3.8.6 Overload protection' malfunctions detected (in cooling or dehumidifying mode)
If it is detected that the unit enters overload protection 6 times because the condenser tube temperature is superheating in cooling or
dehumidifying mode, the dual-8 nixie tube shows E8.
3.8.7 Defrosting' malfunctions detected
For ensusing heating effect, air conditioner will defrost automatically according to defrosting status on outdoor unit. heating indicator
flashes, 10 seconds and stop 0.5 seconds circularly.
.
4. Troubleshooting
4.1 Problem1: air conditioner does not start and the buzzer does not ring
What to do: check the air conditioner plug or replace the controllers.
Technical Information
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