29
Installation and Maintenance
20
Compressor phase
current overcurrent
protection
P5
Cooling: compressor and outdoor fan stop,
while indoor fan operates
Heating: compressor, outdoor fan and
indoor fan stop
1. Control board and compressor are reliably connected?
Is it loose? Connection sequence is correct?
2. Compressor coil resistance is normal? Insulation of
compressor coil to copper pipe is good?
3. Outdoor fan is abnormal?
4. Big or small valve is not open, system is stuck,
condenser is blocked with dirt or ventilation is poor?
5. Unit voltage input is in normal range (voltage between L
and N)?
6. Mainboard power module is damaged?
7. Indoor or outdoor ambient temperature is too high?
8. Compressor is stuck?
21
Module temperature
sensor circuit
malfunction
P7
Cooling: compressor and outdoor fan stop,
while indoor fan operates
Heating: compressor, outdoor fan and
indoor fan stop
Malfunction of module temperature sensor, replace the
mainboard.
22
High module
temperature
protection
P8
Cooling: compressor and outdoor fan stop,
while indoor fan operates
Heating: compressor, outdoor fan and
indoor fan stop
1. Check if the ventilation of radiator is normal. If it is
abnormal, please improve it.
2. After cutting o the power of the whole unit for 20min,
check if the thermal grease of IPM module on the ODU
control board is dry and if the radiator is tightened?
3. If there is no problem after checking the above two
points, please replace the ODU control board.
23
DC bus voltage is too
low
PL
Cooling: compressor, outdoor fan and
indoor fan stop
Heating: compressor, outdoor fan and
indoor fan stop
1. Measure the power supply voltage to see if it is too
low or it is dragged down as the power supply capacity is
insucient?
2. For the model with reactor, check if the reactor
connection is good?
3. Mainboard is damaged?
24
DC bus voltage is too
high
PH
Cooling: compressor and outdoor fan stop,
while indoor fan operates
Heating: compressor, outdoor fan and
indoor fan stop
1. Measure the power supply voltage to see if it is too high
or there is fluctuation?
2. Mainboard is damaged?
25
Malfunction of
compressor phase
current detection
circuit
U1
Cooling: compressor and outdoor fan stop,
while indoor fan operates
Heating: compressor, outdoor fan and
indoor fan stop
Mainboard is damaged, replace the outdoor control board.
26
DC bus voltage drop
malfunction
U3
Cooling: compressor and outdoor fan stop,
while indoor fan operates
Heating: compressor, outdoor fan and
indoor fan stop
Power supply voltage is unstable with big fluctuation
To Next Page
Loading...
