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32
DIAGNOSIS AND SOLUTION (CONT)
Index 1
1 Indoor or Outdoor DC Fan Motor (control chip is in fan motor)
S
Power on and when the unit is in standby, measure the voltage of pin1−pin3, pin4−pin3 in fan motor connector. If the voltage value
is not in the range shown in Table 18 or Table 19, the PCB has an issue and needs to be replaced.
Fig. 34 – Motor Connector
Table 18—DC motor voltage input and output (voltage: 220−240V~)
NO.
COLOR
SIGNAL
VOLTAGE
1
Red
Vs/Vm
280V~380V
2
---
---
---
3
Black
GND
0V
4
White
Vcc
14-17.5V
5
Yellow
Vsp
0~5.6V
6
Blue
FG
14-17.5V
Table 19—DC motor voltage input and output (voltage : 115V~)
NO.
COLOR
SIGNAL
VOLTAGE
1
Red
Vs/Vm
140V~190V
2
---
---
---
3
Black
GND
0V
4
White
Vcc
14-17.5V
5
Yellow
Vsp
0~5.6V
6
Blue
FG
14-17.5V
2 . Outdoor DC Fan Motor (control chip is in the outdoor PCB)
S
Power on the unit and check if the fan runs normally. If the fan runs normally, the PCB has an issue and needs to be replaced. If the
fan does not run normally, measure the resistance of each two pins. If the resistance is not equal to each other, the fan motor has an
issue and needs to be replaced, otherwise the PCB has an issue and needs to be replaced.
3 Indoor AC Fan Motor
S
Power on the unit and set the unit in FAN mode at the high fan speed. Run for 15 seconds then measure the voltage of pin1 and
pin2. If the voltage value is less than 100V(208~240V power supply) or 50V(115V power supply), the PCB has an issue and needs
to be replaced.
Summary of Contents for 38MHRB series
Page 7: ...7 DIMENSIONS OUTDOOR CONT Unit inch mm Fig 3 Size 24K...
Page 11: ...11 WIRING DIAGRAMS COOLING ONLY Fig 7 Wiring Diagram Size Cooling Only Size 12K 115V...
Page 12: ...12 WIRING DIAGRAMS COOLING ONLY CONTINUED Fig 8 Wiring Diagram Cooling Only Size 12K 230V...
Page 13: ...13 WIRING DIAGRAMS COOLING ONLY CONTINUED Fig 9 Wiring Diagram Cooling Only Sizes 18 24K...
Page 14: ...14 WIRING DIAGRAMS HEAT PUMP Fig 10 Wiring Diagram Heat Pump Size 12K 115V...
Page 15: ...15 WIRING DIAGRAMS HEAT PUMP CONTINUED Fig 11 Wiring Diagram Heat Pump Sizes 09 12 18 230V...
Page 16: ...16 WIRING DIAGRAMS HEAT PUMP CONTINUED Fig 12 Wiring Diagram Heat Pump Size 24 230V...
Page 37: ...37 DIAGNOSIS AND SOLUTION CONT Fig 36 P U Fig 37 P V...
Page 38: ...38 DIAGNOSIS AND SOLUTION CONT Fig 38 P W Fig 39 N U...
Page 39: ...39 DIAGNOSIS AND SOLUTION CONT Fig 40 N V Fig 41 N W...