13.2
Protection Control for Heating Operation
13.2.1 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.
13.2.2 Deice Operation
When outdoor pipe temperature and outdoor air temperature is low, deice operation start where outdoor fan motor
stop.
Deice judging condition
Outdoor Unit Deice Control
10
5
0
-5
-10
-15
-20
-25
-30
-30
Deice operation time diagram
a. Deice mode 1 control:
Free
Compressor
Four way valve
ID pump
OD fan
Expansion valve
Free
-20
-10
Outdoor Temperature (°C)
1
2
ON
ON
Free
When Heating Time > 35 minutes
and Pipe Temperature below this
line for continuous 3 minutes.
0
10
3
5
4
OFF
O
N
OFF
max 9 minutes 30 seconds
deice 1
127
Deice starts depends:
1. Outdoor air sensor temp.
2. Outdoor pipe sensor temp.
3. Heating accumulation time.
20
30
6
7
Free
8
9
ON
O
N
Free