E2, E3, E4 Troubleshooting - Midea MDV-D22Q1/N1-D Technical Manual

3.4.

E2, E3, E4 Troubleshooting

3.4.1. Display output
or
or
or
3.4.2. Description
▪ E2 indicates an indoor ambient temperature sensor error.
▪ E3 indicates an indoor heat exchanger mid-point temperature sensor error.
▪ E4 indicates an indoor heat exchanger outlet temperature sensor error.
3.4.3. Impact on other units
▪ Refer to
4.2 "Impact on Other
3.4.4. Possible causes
▪ Temperature sensor not connected properly or has malfunctioned.
▪ Damaged main PCB.
3.4.5. Procedure
Temperature sensor connection on
main PCB is loose
Temperature sensor has short-
circuited or failed
Replace indoor main PCB
Notes:
1. The indoor ambient temperature sensor connection port, indoor heat exchanger mid-point temperature sensor connection port and indoor heat
exchanger outlet temperature sensor connection port on each type of indoor unit main PCB are labeled in Figures 1.1 to 1.19 in
2. Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor's resistance
characteristics table, the sensor has failed. Refer to Table 6.1 in
OPERATION LED
flashes twice per
second
OPERATION LED
flashes twice per
second
OPERATION LED
flashes twice per
second
Units".
E2 / E3 / E4
1
No
2
No
Ensure the sensor is connected
Yes
Yes
6.1 "Temperature Sensor Resistance
properly
Replace the sensor
Characteristics".
1, "Main PCB Ports".