145
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
-30
-30
-20
-10
0
10
20
30
-25
-20
-15
-10
-5
0
5
10
O
D
P
ipe T
e
m
p
er
at
ur
e (
°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:
Deice mode selection condition
o
There are 2 deice modes, according to water inlet temperature and outdoor ambient temperature the deice
mode is decided.
50°C
27°C
-
10°C
Water inlet temperature
Outdoor ambient temperature
Deice mode 1
Deice mode 2
Judgement details:
1) When water inlet temperature is more than 50°C, unit will operate deice mode 1.
2) When water inlet temperature is less than 27°C, unit will operate deice mode 2.
3) When water inlet temperature is less than 50°C and outdoor ambient temperature is less than -10°C, unit will
operate deice mode 2.
4) When water outlet temperature sensor 2 detect temperature is less than 22°C, unit will operate deice mode 2.
