Hitachi YUTAKI Series - Page 181

179
Troubleshooting procedure
SMGB0066 rev.0 - 12/2009
Troubleshooting
Service Manual
7
 

↔


• ThealarmcodeisdisplayedonthePCB´sdisplay.
• Duringnormaloperation,(incoolingoheatingoperationmode)theElectronicControlstopsandrestartsautomatically
after 3 minutes.
• TheStopalarmappearsafter3retriesduring30minutes.
– Thisalarmcodeisdisplayedwhenthehighpressure(Pd)isincresedtomorethan3.9MPa,during10secondsin
compressorrunningfrequencymorethan40Hzor,
– Thisalarmcodeisdisplayedwhenthehighpressure(Pd)isincresedtomorethan3.5MPa,during10secondsin
compressor running frequency lees than 40 Hz.



note
In case that the low pressure is higher than 2.2 MPa, segment shows 2.2 MPa. -
In this case, connect a pressure gauge to high pressure check joint, check the pressure shown in the gauge. -
Are connector CN4 on the
Printed circuit Board (PCB1)
and High Pressure Sensor
correctlyconnected?
Wiring Check and Repair
No
Yes
No
Yes
Is DIP switch DSW8 on the
Printed Circuit Board (PCB1)
correctlyset?
See Test run procedure for
Yutaki for correct setting
Check DIP switch setting and
set it correctly
Are High Pressure and Low
Pressure shown in segment
as "Pd" and "Ps" almost
coincident during compressor
stop?
Yes
See Failure Analysis
No
Is high pressure sensor
output character and Low
Pressure sensor display value
"Ps" proper during compressor
Stop?(Outputcharactershown
in chapter "High Pressure
Sensor Abnormal")
Yes
Failure of component on
PCB1. Replace PCB1
No
Is the voltage between
VCC05T and GND1 on PCB1
5V?.RefertoVoltageTest
Position
No
Failure of Power
Supply Circuit on PCB1.
Replace PCB1
Yes
Failure of High Pressure
Sensor