Eco Air CTBU-09HWFN1-M(C), Service Manual, Page: 106 / 219

103
---
4°C(39.2°F)≤T2≤7°C(44.6°F), the
compressor will keep the current frequency.
---T2>7°C(44.6°F), the compressor frequency
will not be limited.
15.4 Operation Modes and Functions
15.4.1 Fan mode
(1) Outdoor fan and compressor stop.
(2) Temperature setting function is disabled,
and no setting temperature is displayed.
(3) Indoor fan can be set to high/med/low/auto.
(4) The louver operates same as in cooling
mode.
(5) Auto fan:
a
b
c
d
6 .0 °C ( 1 0 .8 °F )
T 1 - 2 4 °C ( 7 5 .2 °F )
e
H
( H - L ) * 0 .7 5 + L
( H - L ) * 0 .5 + L
( H - L ) * 0 .2 5 + L
L
5 .0 °C ( 9 °F )
4 .0 °C ( 7 .2 °F )
2 .5 °C ( 4 .5 °F )
1 .0 °C ( 1 .8 °F )
15.4.2 Cooling Mode
15.4.2.1 Outdoor fan running rules
T4
A DC_FAN_HI_SPD_ADD
B DC_FAN_MID_SPD_ADD
C DC_FAN_MIN_SPD_ADD
D DC_FAN_SLOW_SPD_ADD
E DC_FAN_SSLOW_SPD_ADD
28
℃
(82.4°F)
19
℃
(66.2°F)
17
℃
(62.6°F)
26
℃
(78.8°F)
25
℃
(77°F)
23
℃
(73.4°F)
22
℃
(71.6°F)
20
℃
(69°F)
15.4.2.2 Indoor fan running rules
In cooling mode, indoor fan runs all the time
and the speed can be selected as high,
medium, low and auto.
The indoor fan is controlled as below:
Setting fan
speed
Actual fan speed
H+(H+=H+G)
A H（=H）
B
C
M+(M+=M+Z)
D M(M=M)
E
F
L+(L+=L+D)
G L(L=L)
H
I
T1-Td
℃
(°F)
L
L-(L-=L-D)
H
H-（H-=H-G)
M
M-(M-=M-Z)
4.5(8.1)
3.0(5.4)
1.5(2.7)
4.5(8.1)
3.0(5.4)
1.5(2.7)
4.5(8.1)
3.0(5.4)
1.5(2.7)
Auto fan in cooling mode acts as follow:
a
b
c
d
6 .0 °C ( 1 0 .8 °F )
T 1 - T d
e
H
( H - L ) * 0 .7 5 + L
( H - L ) * 0 .5 + L
( H - L ) * 0 .2 5 + L
L
5 .0 °C ( 9 .0 °F )
4 .0 °C ( 7 .2 °F )
2 .5 °C ( 4 .5 °F )
1 .0 °C ( 1 .8 °F )
15.4.3 Heating Mode
15.4.3.1 Outdoor fan running rules
T4
E DC_FAN_SSLOW_SPD_ADD
D DC_FAN_SLOW_SPD_ADD
C DC_FAN_MIN_SPD_ADD
B DC_FAN_MID_SPD_ADD
A DC_FAN_HI_SPD_ADD
15
℃
(59°F)
13
℃
(55.4°F)
12
℃
(53.6°F)
10
℃
(50°F)
21
℃
(69.8°F)
19
℃
(66.2°F)
18
℃
(64.4°F)
16
℃
(60.8°F)
15.4.3.2 Indoor fan running rules
When the compressor is on, the indoor fan can
be set to high/med/low/auto. And the anti-cold
wind function has the priority.
The indoor fan is controlled as below:
Setting fan
speed
Actual fan speed
H
（
=H
）
H+(H+=H+G)
M(M=M)
M+(M+=M+Z)
L(L=L)
L+(L+=L+D)
H-
（
H-=H-G)
M-(M-=M-Z)
L-(L-=L-D)
T1-Td+1.5
℃
(34.7°F)
L
H
M
-1.5(-2.7
°
F)
-3.0(-4.8
°
F)
-4.5(-8.1
°
F)
-
-1.5(-2.7
°
F)
-3.0(-4.8
°
F)
-4.5(-8.1
°
F)
-1.5(-2.7
°
F)
-3.0(-4.8
°
F)
-4.5(-8.1
°
F)
Auto fan action in heating mode: