Gree GMV-VQ680WM/C-X Service Manual page 186

Gree
2.120 "L2" E-heater Protection (Reserved Code, Not Yet Applied)
2.121 "L3" Overflow Protection
Fault display: wired controller of indoor unit and receiver of indoor unit display
Applicable models: all indoor units
Fault diagnosis:
When the water level is too high, the float switch of indoor unit will be triggered for overflow
protection.
Possible causes:
■ The indoor unit is installed improperly;
■ The drain pump is damaged;
■ The float switch operates improperly;
■ The main board of indoor unit operates improperly.
Troubleshooting:
"L3" Overflow Protection
Is the faulty unit provided with a water
pump?
Yes
Is the water pump a built-in one?
Yes
If the level of water in the drainage pan is
high but the float switch works normally,
check whether the drain pump is working
normally
Yes
Whether the drain pipe is
abnormal?
Yes
The drain pipe's hoisting
height may exceed that of
the drain pump, and the
drain pipe may be clogged
If the indoor unit is not provided
with a built-in drain pump, the
No water pump's output end is
suspended and the float switch is
short circuited (for details, see the
circuit diagram of the indoor unit)
If the level of water in the drainage
pan is very low or there is no water
Ye
at all, or the indoor units report full
s
water protection after being
powered on, it may indicate a faulty
float switch. In this case, check
whether the float switch is clogged
184
GMV6 HR DC Inverter VRF Units Service Manual
Whether the float switch
jumper is connected reliably?
Looseness, oxidation or poor
Yes
contact of jumpers may
misleadingly trigger full water
protection