Midea MCHS-09PSH1, Service Manual

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T3
Resume
Off
Decrease
Hold
When condenser temperature temp. is more
than setting value, the compressor will stop.
8.4.2.5 Evaporator temperature protection
When Evaporator temperature temp.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
S
<ΔT-1.5
时，
the compressor will be
on.
ΔT is the programmed parameter of
temperature compensation.
When the AC run in mute mode, the
compressor will run with low frequency.
When the current is more than setting value,
the current protection function will be activated
and the compressor will stop.
8.4.3.2 Outdoor fan running rules
The outdoor unit will be run at different fan
speed according to T4.
For different outdoor units, the fan speeds are
different
T 4
E
D
C
B
A
A +
8.4.3.3 Indoor fan running rules
When the compressor is on, the indoor fan can
be set to high/med/low/auto/mute.
When indoor unit coil temp. is low, the anti-cold
air function will start and indoor fan motor will
run at low speed, the speed can’t be
changed ,when the temp. is lower than setting
value, the indoor fan motor will stop.
When the indoor temp reaches the setting
temp., the compressor will stop, the indoor fan
motor will run at the minimum speed or setting
speed.(The anti-cold air function is valid).
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
℃
L
H
M
-
Auto fan action in heating mode:
T 1 - T d + Δ T
8.4.3.4Defrosting mode
AC will enter the defrosting mode according to
the value of temp. of T3 and the value range of
temp. change of T3 and also the compressor
running time.
During the defrosting mode, the compressor
keep running, indoor and outdoor motor will stop,
defrost lamp of the indoor unit will be lighted