DM14-01.01.18en
MIV V5 Heat Recovery DC Inverter R410A
175
Troubleshooting
4.17 P5: Condenser temperature protection
When condenser temperature is over 65
o
C, the system will display P5 protection, the ODU in standby. When
the temperature goes back to normal range, P5 disappear and normal operation resumes.
Note:
1. How to check whether the T3/T5 sensor is circuit or disabled
①
:
Using a multimeter 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 1, the sensor is disabled
2. The phenomenon of the indoor load is too large
②
:
The suction temperature and discharge temperature are both higher than normal value.
3. The phenomenon of The high pressure side of the system is blocked
③
:
The high pressure is higher than normal value, the low pressure is lower than normal value, and the discharge temperature is
higher than normal value.
4. The phenomenon of the system contains air or nitrogen
④
:
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.
P5: Condenser temperature protection
T3/T5 port on main control board is loose
Fasten the T3/T5 port
T3/T5 sensor is short circuit or disabled
①
Replace the sensor
Yes
Yes
The indoor load is too large
②
Make sure the ratio of connectable
IDU is less than 130% or add ODU
No
Yes
No
The heat exchange of condenser
is not good. It may be caused by
dirty heat changer, abnormal ODU
fan running, ODU are too near to
each other, etc.
Check the system and
fixed up the error
No
Yes
The high pressure side of the system is
blocked
③
for squashed pipe, blocked
valve or closed stop valve
Make sure all valves are open,
check the system, and remove
the obstacle
System contains air or nitrogen
④
Discharge the entire refrigerant. Then
vacuum the system and refill the
refrigerant. Add oil to the system if it leaks.
Yes
No
Yes
No
No
Discharge the entire refrigerant. Then
vacuum the system and refill the refrigerant.
Add oil to the system if it leaks.
Outdoor main PCB
is damaged
Replace the outdoor
main PCB
