Gree GMV-Pdm450W/NaB-M

DC Inverter Multi
VRF Service Manual
159
S/N Class Trouble
Possible Cause
Troubleshooting
First-level reason Second-level reason Third-level reason
Description of Cause
Method of
Conrmation
Description of Cause
Method of
Conrmation
Description of Cause
Method of
Conrmation
3
Discharge
temp is
abnormal
Discharge
temp is
superhigh
2.Electric expansion
valve does not
correctly operate
In cooling mode,
when electric
expansion valve is
opened to 480PLS,
outlet temp
of coil pipe
of indoor unit is
greater than inlet
temp for over 15
.
In heating mode,
when electric
expansion valve is
opened to 480PLS,
inlet temp
of coil pipe
of indoor unit is
lower than ambient
temp for over 10 .
2.2Electric expansion
valve is abnormal.
De-energize and then
energize the indoor
unit, check if the
electric expansion
valve is reset by
touching pipeline and
hearing the voice. If it
is reset, it is normal.
2.2.1 Control wire of
expansion valve is not
connected with mainboard.
Indoor unit PCB
Coil
Valve
Manually check
Connect control
wire of electric
expansion valve.
4
2.2.2 Control wire of
expansion valve connected
with mainboard is damaged.
PCB
Coil
Valve
Open circuit
Manually check
Repair or
replace control
wire of electric
expansion valve
5
2.3 Electric expansion
valve is abnormal
Not the reason
mentioned above
2.3.1 Foreign objects inside
the system affect it.
——
Clean and blow
the system
to clear the
foreign objects
and meanwhile
replace the
valve body.
6 2.3.2 Valve body is abnormal. ——
Replace the
valve body.