Mitsubishi Electric City Multi CMB-WP108V-G, Service Manual, Page: 220 / 301

[
IX
Troubleshooting ]
- 211 - HWE1113B GB
(5) In the case of SV5b (Bypass valve)
This solenoid valve closes when energized (when the relay is on).
This valve turns off for five minutes after the completion of the defrost cycle, or when SV9 is on turned ON and the value of
63HS1 is greater than 3.5 MPa [507psi] during Heating-only or Heating-main operation at the minimum frequency. The valve
position can be determined by measuring and monitoring the changes in the pipe temperature on the downstream of SV5b
while the unit is de-energized. When the valve is open, high-temperature gas refrigerant passes through the pipe. Do not at-
tempt to check the pipe temperature by touching the pipe.
(6) In the case of SV5c (Bypass valve)
This solenoid valve opens when energized (when the relay is on).
Depending on the conditions only during Cooling-only or Cooling-main operation, the solenoid valves turn on. Check for prop-
er operation on the LED and by listening for the operation sound of the solenoid valves.
(7) In the case of SV9 (Bypass valve)
This solenoid valve opens when energized (when the relay is on)
This valve turns on when the value of 63HS1 is greater than 3.5 MPa [507psi] during Heating-only or Heating-main operation
at the minimum frequency. The valve position can be determined by measuring and monitoring the changes in the pipe tem-
perature on the downstream of SV9 while the unit is energized. When the valve is open, high-temperature gas refrigerant
passes through the pipe. Do not attempt to check the pipe temperature by touching the pipe.
Outdoor Unit Fan
-4- Outdoor Unit Fan
(1) Fan motor
Œ
To check the revolution of the fan, check the inverter output state on the self-diagnosis LED, as the inverter on the outdoor
fan controls the revolutions of the fan. The maximum revolution of the fan is approximately 790 rpm.
Œ
When starting the fan, the fan runs at full speed for 5 seconds.
Œ
When setting the DIP SW1 as shown in the figure below, the inverter output [%] will appear. 100% indicates the full speed
and 0% indicates the stopping.
Œ
As the revolution of the fan changes under control, at the interphase or when the indoor unit operation capacity is low, the
revolution of the fan may change.
Œ
If the fan does not move or it vibrates, fan inverter board problem or fan motor problem is suspected. Refer to IX [4] -7- (2) [5]
"Check the fan motor ground fault or the winding."(page 223) and IX [4] -7- (2) [6] "Check the FAN board failure."(page 223)
O
N
S W1
1 2 3 4 5 6 7 8 9
1
0
O
FF