MCAC-VTSM-2016-02 R410A All DC Inverter Mini VRF
Troubleshooting 69
5.6 E7: Discharge Temperature Sensor Malfunction
1. How to check whether the sensor is normal
①
:
Using a multi-meter to measure resistance, if the resistance is too small, the sensor is short circuit, if the resistance in
certain temperature is not consistent with attached table 2, the sensor is damaged.
2. The phenomenon of the system contains air or nitrogen
②
:
The high pressure is higher than normal value, current is larger than normal value, discharge temperature is higher than
normal value, compressor makes noise, pressure meter do not display steady.
LED
displays
E7
Discharge sensor malfunction.
Check whether discharge temperature sensor
’s head is
inside the sleeve or its wiring is connected to the main PCB
properly.
NO
Connect again.
YES
Check whether the discharged sensor is normal.
①
NO
Replace discharge sensor.
YES
Check the operation conditions of the unit meets the
operation requirement
(
environment temperature,
airflow of the heat exchanger, etc.
)
NO
Belongs to the normal protection.
Check whether the refrigerant is charged too much.
NO
Confirm the refrigerant
’s weight again.
YES
Replace the main PCB.
YES
Check whether the 4-way valve is normal.(No air mixed
up or bad action phenomenon. )
②
NO
Replace 4-way valve.
YES
Summary of Contents for MDV-120W/DON1
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