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6. Room Temperature Thermistor Circuit
●
Fig. 6-1 shows the room temperature
thermistor circuit.
0V
Room
temperature
thermistor
0V
5V
Fig. 6-1
A
R309
C302
Micro
computer
Room
temp. input
R310
0V
Heat exchanger
temperature thermistor
0V
5V
Fig. 7-1
A
R307
C301
Micro computer
Heat
exchanger
temperature
input
R308
5
4
3
2
1
0
0
10
Fig. 6-2
20
30
40
V
oltage at
(V)
A
5
4
3
2
1
0
0
10
-10
Fig. 7-2
20
30
40
V
oltage at
(V)
A
64
63
7. Heat exchanger temperature thermistor circuit
●
The voltage at
A
depends on the room
temperature as shown in Fig. 6-2.
●
The circuit detects the indoor heat
exchanger temperature and controls
the following.
(1) Low-temperature defrosting during
cooling and dehumidifying
operation.
The voltage at
A
depends on the heat
exchanger temperature as shown in
Fig. 7-2.
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 ...