Gree GWH07AAAXA-K3NNA2A - Page 52

49
Installation and Maintenance
Service Manual
No. Malfunction Name
Display Method of
Indoor Unit
A/C status Possible Causes
Dual-8 Code
Display
8
Outdoor discharge
temperature sensor is
open/ short-circuited
F5
The unit will stop operation as it reaches
the temperature point. During cooling and
drying operation, the compressor stops
operation while IDU fan motor operates;
During heating operation, the heating fan
motor operates according to the conditions
of blowing residual heat.
1. The wiring terminal between outdoor
condenser temperature sensor and
maiboard is loosened or poorly contacted.
2. There’s short circuit due to trip-over of
the parts on maiboard.
3. Outdoor condenser temperature sensor
is damaged (Please check it by referring
to the resistance table for temperature
sensor).
4. Mainboard is broken.
9
High pressure
protection
E1
During cooling and drying operation,
except indoor fan operates, all loads stop
operation. During heating operation, if it
is inverter unit, the complete unit stops; if
it is oor standing unit, the complete unit
stops and operation of remote controller or
controller is unavailable.
1. The main board and the display panel
are not connected well.
2. The OVC terminal on main board is
not connected well with the high pressure
switch on the complete unit.
3. The wiring of high pressure switch is
loosened.
4. Refrigerant is superabundant;
5. Poor heat exchange (including blocked
heat exchanger and bad radiating
environment );
6. Ambient temperature is too high; (if it is
3-phase unit, the high pressure protection
may be caused by overcurrent protection
due to this reason)
7. The supply voltage is abnormal (if it is
3-phase unit, the high pressure protection
may be caused by overcurrent protection
due to this reason)
8. The air intake and air discharge at indoor
/ outdoor heat exchanger are not smooth.
The air cycle is short circuited.
9. Filter and heat exchange ns of indoor/
outdoor units are blocked.
10. The system pipeline is blocked.
11. The gas valve and liquid valve for
outdoor unit are not completely opened.
12. The OVC input is at high level.
10
Low pressure
protection of
compressor
E3 The complete unit stops
1. The main board and display panel are
not connected well.
2. The LPP terminal on the main board is
not connected well with the high pressure
switch on the complete unit.
3. The wiring of the high pressure switch is
loosened. High pressure switch is damaged
or poorly contacted.
4. Insufcient or leaking out refrigerant.
5. The LPP input is at high level.
11
High discharge
temperature protection
of compressor
E4
During cooling and drying operation,
compressor and outdoor fan stop while
indoor fan operates. During heating
operation,all loads stop.
1. Abnormal system (e.g.: blockage, etc)
2. Abnormal rotation speed of outdoor
motor (cooling )
3. Abnormal air intake (cooling)
4. System is normal, but the compressor
discharge temperature sensor is abnormal
or poorly contacted.