Hitachi RAC-25JX4, Service Manual

Page: 97 / 119

Ð 102 Ð
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[A. Control P.W.B.]
Remove four screws securing the control
P.W.B. to the cooling fins, andremove the
control P.W.B. from the cooling fins.
1
[B. Power P.W.B.]
Open the support latches andraise the
power P.W.B. in the direction of the arrow as
shown in Fig. A.
1
Open the support latches andraise
the control P.W.B. in the direction of
the arrow as shown in Fig. A.
2
<Direction of the control P.W.B. removal>
<Direction of the power P.W.B. removal>
Be sure that the power switch is turnedoff or the power cable is disconnectedbefore servicing.
System Configuration of Outdoor Unit Electrical Parts
<Control P.W.B. (M board)>
Contains a rectifier circuit andinverter module, their controlling microcomputer and
microcomputer peripheral control circuits.The boardincorporates high andlow current sections.
<Power P.W.B. (P board)>
Contains a switching power circuit, noise filter, power factor improvement circuit, etc.
The switching power circuit supplies power to electronic circuits on the control P.W.B. through
CN3.
When replacing any P.W.B., disconnect all the cables (including ground wires).
The outdoor unit electrical parts consist of two P.W.B.s as shown in the figure.
Fig. A
Open these support latches to
remove the power P.W.B.
Open these support latches to
remove the control P.W.B.