Carrier 38MARBQ12AA1 Service Manual page 26

Indoor Fan Running Rules:
When the compressor is on, the user can set the indoor fan to either
HIGH/MED/LOW/AUTO/MUTE. When the indoor unit coil
temperature is low, the anti-cold air function starts and the indoor fan
motor runs at the low speed. The speed can not be changed.
When the temperature is lower than the setting value, the indoor fan
motor stops. When the indoor temperature reaches the setting
temperature, the compressor stops, the indoor fan motor runs at the
minimum speed or setting speed. The anti-cold air function is valid.
The indoor fan is controlled as shown in Fig. 31.
Setting Fan
T1-Td+34.7°F (1.5 °C)
Speed
-2.7°F(-1.5°C)
H
-5.4°F (-3.0°C)
-8.1°F(-4.5°C)
-2.7°F(-1.5°C)
M
-5.4°F (-3.0°C)
-8.1°F(-4.5°C)
-2.7°F(-1.5°C)
L
-5.4°F (-3.0°C)
-8.1°F(-4.5°C)
Fig. 31 —Indoor Fan Running Rules
26
Auto fan action in the HEATING mode.
T1-Td +3F (1.5C)
-1.8F(-1.0°C)
-3.6°F(-2.0°C)
-5.4°F(-3.0°C)
-7.2°F(-4.0°C)
Actual Fan
-9°F(-5.0°C)
Speed
-10.8°F(-6.0°C)
-11.7°F(-6.5°C)
H - (H-=H-G)
H (=H)
H + (H+ =H+G)
Fig. 32 —Auto Fan Action in HEATING Mode
M - (M-=M-Z)
M (M=M)
M + (M+ =M+Z)
L - (L-=L-D)
L (L=L)
L + (L+ =L+D)
Specifications subject to change without notice.
0°F(0.0°C)
L
(H+-L)*0.2+L
(H+-L)*0.4+L
(H+-L)*0.6+L
(H+-L)*0.8+L
H+
SG-38MARB-01