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15.2 Protection Control for Heating Operation
15.2.1 Outdoor Air Temperature Control
The maximum current value is regulated when the outdoor air temperature rises above 14°C in order to avoid
compressor overloading.
15.2.2 Deice
Operation
When outdoor pipe temperature and outdoor air temperature is low, deice operation start where outdoor fan motor
stop.
Normally, deice start if pipe sensor temperature fulfil deice condition. If remote controller set to AUTO force defrost
setting, unit will start force deice after heat pump operate for 3 hours without deice at below outdoor temperature 5°C.
Deice judging condition
Deice operation time diagram
a. Deice mode 1 control:
15.2.3 Force Defrost Operation
Force defrost can be set through remote control with two selection (Manual OR Auto).
If Manual defrost set, heat pump only run force defrost at heat mode when force defrost request from quick menu
remote control.
If Auto defrost set, heat pump automatically run force defrost operation after 3 hours heating accumulation time
without defrost when ambient below 5°C.
-30
-30
-20
-10
0
10
20
30
-25
-20
-15
-10
-5
0
5
10
O
D
P
ipe
T
e
m
p
e
rat
u
re (
°C
)
Outdoor Unit Deice Control
line for continuous 3 minutes
and Pipe Temperature below this
When Heating Time > 35 minutes
Outdoor Temperature (°C)
3. Heating accumulation time
1. Outdoor air sensor temp.
2. Outdoor pipe sensor temp.
Deice start depends:
OD fan
ID pump
Expansion valve
Four way valve
Compressor
Free
Free
ON
OFF
OFF
N
O
N
O
Free
5
7
6
4
9
8
3
2
1
ON
ON
Free
Free
Max 9 mins 30 secs
deice 1