Hitachi RAF-35RPA RAF35RPA User Manual

Product codes

RAF35RPA

TROUBLESHOOTING

14-16

14.4.2 INDOOR FAN DOES NOT OPERATE (OTHERS ARE NORMAL) – RAK-25/35/50PXA, RAK-

18/25/35/50/70PPA, RAK-18/25/35/50PEA, RAF-25/35/50RPA, RAF-25/35/50PXA, RAD-50/60/70PPA

Yes

Replace the fan motor

Replace the microcomputer

Can the fan be stopped
by remote control?

Replace the microcomputer

The microcomputer fan PWM
output at pin (24) is 1-5V

Perform final operation check

14.4.3 AIR DEFLECTOR DOES NOT MOVE (OTHERS ARE NORMAL)

Yes

Are pulse signals output at
microcomputer pin ⑮~⑱ when auto
swing is turned ON in the fan mode?

Replace the microcomputer

Replace IC111

Is voltage over 15 or below 10V
being generated on the 12V line?

Check IC711. If it is
normal, replace the air
deflector motor

Perform final operation check

14.4.4 CHECK THE CONTROL P.W.B. (POWER CIRCUIT) – RAK-25/35PXA, RAK-18/25/35PPA, RAK-

18/25/35/50PEA, RAF-25/35/50RPA, RAF-25/35PXA

Yes

Is 35V or 20V being output at pinn⑤
relative to 0V at pin③ of CN3

Check to see if the connection cables
are disconnected or reversed. If
normal, check the outdoor unit P.W.B.

Is DC5V being
generated?

Replace IC121. Check if a
short occurs in the 5V
line. If the 5V line is
shorted, ICP1 will open
again.

Is 12V or 7V being output
at (+) relative to 0V at (-)
of C114

Replace ICP1. Check if the air
deflector motor is shorted
and IC111, Q111, C114, ZD121
are defective.

Is CP1 normal? Normal if
it is less than 1

Ω . Blown

(open) if it is 1

Ω or more.

Replace the terminal
board. Insert the
connection cable
securely.

Has the terminal board
thermal fuse blown
(open)?

Replace Q111 and IC111

Perform final operation
check

Yes

Yes (Normal)

Yes

(Open)

Yes

※2

※1

※1: When the unit is not in operation, the voltage across the 35V line may drop to 20V
※2: When the unit is not in operation, the voltage across the 12V line may drop to 7V