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1. Power does not come on (no operation)
Is AC 220-240V AC being generated
between terminals L and N on the
outdoor unit terminal board?
Is DC 35V being generated between
terminals C and D on the outdoor
unit terminal board?
Check the indoor/outdoor unit
connection cable, and correct any
defective section (wrong connection,
incomplete insertion reversed).
Check AC outlet and breaker, and
repair any defective part.
Check the outdoor unit power circuit,
and repair the defective section.
Is DC 35V being generated between
terminals C and D on the terminal
board?
Are control voltages (12V, 5V)
being generated normally?
Check according to the proper method
for checking the power circuit.
No
No
No
No
Yes
Yes
Do the air deflectors perform initial
operation when the power supply is
turned on and off?
Check the indication P.W.B.
connection cord and light receiving
unit.
No
No
Is the microcomputer reset input
(pin 7 ) Hi ?
Replace the control P.W.B
Perform final operation check.
Check the reset circuit, and repair
any defective section.
Yes
No
Is the microcomputer clock signal
10MHz at pin
10
11
being
generated normally?
Replace the microcomputer and
oscillator.
Yes
Yes
Yes
CHECKING INDOOR UNIT ELECTRICAL PARTS
Summary of Contents for RAC-70YH7
Page 35: ... 35 CIRCUIT DIAGRAM Remote Control ...
Page 36: ... 37 CIRCUIT DIAGRAM MODEL RAS 70YH7 ...
Page 37: ... 39 CIRCUIT DIAGRAM MODEL RAC 70YH7 ...
Page 39: ... 42 MODEL RAC 70YH7 P W B MAIN ...
Page 40: ... 43 P W B IPM BOARD P W B NF BOARD ...
Page 42: ... 45 51 53 53 55 57 49 29 66 23 25 25 25 25 ...
Page 46: ... 53 ...
Page 56: ... 66 220 240 220 240 3 15A RAC 70YH7 ...
Page 57: ... 67 AC220 240V DC260 360V ...
Page 58: ... 68 C001 C007 C015 C016 C026 C027 L004 L005 J25 J25 J25 J23 J58 J25 ...
Page 60: ... 70 ...
Page 61: ... 71 ...
Page 62: ... 72 3 15A Fuse ...
Page 63: ... 73 3 15A 3 15A DC260 360V ...
Page 66: ... 76 ...
Page 67: ... 77 ...
Page 68: ... 78 TROUBLE SHOOTING ...
Page 69: ... 79 DISCHARGE PROCEDURE AND METHOD TO STOP ENERGIZE THE POWER CIRCUIT ...
Page 70: ... 80 ...
Page 75: ... 85 2 Outdoor unit does not operate but receives remote infrared signal ...
Page 80: ... 90 AC220 240V AC240V P W Bs P W Bs Replace outdoor P W B Main P W Bs ...
Page 81: ... 91 Replace outdoor P W B Main Replace fan motor Replace outdoor P W B Main ...
Page 83: ... 93 ...
Page 84: ... 94 ...
Page 86: ... 96 CHECKING THE REMOTE CONTROLLER ...
Page 92: ...PM NO 0465E Printed in Malaysia RAS 70YH7 RAC 70YH7 ...