Operation Modes And Functions; Fan Mode; Cooling Mode; Heating Mode - Century B-VMH36SD-1 Service Manual

8.4 Operation Modes and Functions

8.4.1 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:
T1
a
b
c
d
e

8.4.2 Cooling Mode

8.4.2.1 Compressor running rules
When T1-Ts<-2℃(28.4°F), the compressor will
stop, when T1—T >-0.5℃(31.1°F), the
S
compressor will be activated.
When the AC runs in mute mode, the
compressor will run at low frequency. When
the current is more than set value, the current
protection function will be activated, and the
compressor will stop.
8.4.2.2 Outdoor fan running rules
The outdoor unit will be run at different fan
speeds according to T4.
For different outdoor units, the fan speeds are
different.
T 4
A +
A
B
C
D
E
8.4.2.3 Indoor fan running rules
In cooling mode, indoor fan runs all the time
and the speed can be selected as high,
Service Manual - VMH 9/12/18/24 SU & VMH30/36S D Series
medium, low and auto.
When the setting temp. is reached, if the
compressor stops running, indoor fan motor
will run in Minimum speed or set speed. The
indoor fan is controlled as below:
Setting fan
T1-Td ℃(°F)
speed
A
H
B
C
D
M
E
F
G
L
H
I
The auto fan acts as below rules:
T1
a
b
c
d
e
8.4.2.4 Condenser temperature protection
T3
Off
Decrease
Hold
Resume
When condenser temperature temp. is
more than setting value, the compressor will
stop.
8.4.2.5 Evaporator temperature protection
When Evaporator temperature is less than
setting value, the compressor will stop.

8.4.3 Heating Mode

8.4.3.1 Compressor running rules
When T1-Ts>-ΔT, the compressor will stop,
when T1-T <ΔT-1.5，the compressor will be
S
on.
ΔT is the programmed parameter of
temperature compensation.
16
18
Actual fan speed
H+(H+=H+G)
H（=H）
H-（H-=H-G)
M+(M+=M+Z)
M(M=M)
M-(M-=M-Z)
L+(L+=L+D)
L(L=L)
L-(L-=L-D)