Midea MCH2U-18PHH2 Service Manual page 21

Exit low ambient cooling
mode , run with high fan
38
for 1 minute
27
Low
off
T3
LowCoolT3_ON
Keep current fan speed
LowCoolT3_Down
Decrease fan speed
LowCoolT3_OFF
Fan stop
6.4.3.2 Heating Mode
Under normal operating conditions, the
system chooses a running fan speed
according to ambient temperature:
30
23
Increase fan speed increase
Outdoor temperature℃
21
19
18
16
15
13
12
10
0
-2
6.4.4 Electronic Expansion Valve (EXV)
Control
1. EXV remains fully closed while the device
is powering up.
standby with 350P open. It opens to the
target angle after the compressor starts.
2. EXV closes with -160P when the
compressor stops. Then it remains on
standby with 350P open. It opens to the
target angle after the compressor starts.
3. The action priority for the EXVs is A-B-C-
D-E.
4. The compressor
commence operation
initializes.
6.4.4.1 Cooling Mode
The initial open angle of the EXV depends on
the size of the indoor model. The adjustment
range is 100-400p.
When the unit has been running for 3
minutes, the outdoor receives indoor units'
capacity demand and T2B information and
then calculates
comparing each indoor's T2B with the
21
Breeze fan speed
Supper low fan speed
Low fan speed
Middle fan speed
High fan speed
Supper high fan speed
EXV then remains on
and outdoor
only after EXV
their average. After
fan