Service manual
DM15-01.01.11-01en
48
Multi DC inverter R410A. Outdoor unit
Heating mode:
Current frequency
（
Hz
）
Current limit value
（
A
）
Frequency limit
HEAT_F16
IHEATLMT12
Decrease the frequency to HEAT_F4 and run at HEAT_F4 for
3 minutes.
After that, the frequency will be adjusted according to the
capacity demand and rise to the upper level every 3 minutes
(When the frequency>Heat_F4 via capacity demand).
HEAT_F15 IHEATLMT11
HEAT_F14 IHEATLMT10
HEAT_F13 IHEATLMT9
HEAT_F12 IHEATLMT8
HEAT_F11 IHEATLMT7
HEAT_F10 IHEATLMT6
HEAT_F9 IHEATLMT5
HEAT_F8 IHEATLMT4
HEAT_F7 IHEATLMT3
HEAT_F6 IHEATLMT2
HEAT_F5 IHEATLMT1
If the current frequency is lower than HEAT_F4, the frequency will not be limited.
After 10s of the compressor start, if the current>IHEAT, the AC will display the failure for 30 seconds and stop. The AC
will restart 3 minutes later.
10.5.5 Indoor / outdoor units communication protection
If the indoor units can not receive the feedback signal from the outdoor units for 2 minutes, the AC will stop
and display the failure.
10.5.6 High condenser coil temp. protection.
When T3>65 for 3 seconds, the compressor will stop while the indoor fan and outdoor fan will continue.
When T3<52 , the protection will release and the compressor will restart after 3 minutes.
10.5.7 Outdoor unit anti-freezing protection
For other models: When T2B<0 for 250 seconds, the indoor unit capacity demand will be zero and resume
to normal when T2B>10 .
For M2OD-16HFN1-Q
，
M2OD-18HFN1-Q
，
M5OD-42HFN1-Q: When T2<4
℃
for 250 seconds or T2<0
℃
,
the indoor unit capacity demand will be zero and resume to normal when T2>8
℃
and the time of protection
is no less than 3 minutes.
10.5.8 Oil return
Running rules:
1. If the compressor frequency keeps lower than RET_OIL_FREQ1_ADD for RET_OIL_TIME1_ADD, the
AC will rise the frequency to RET_OIL_FREQ2_ADD for RET_OIL_TIME2_ADD and then resume to
former frequency.
2. The EXV will keep 300p while the indoor units will keep the current running mode.
If the outdoor ambient is higher than TempT4HeatLimit_ADD during the oil return, the AC quit oil return.
