Daikin BPMK928B42, Service Manual

Page: 148 / 410

Si18-201 System control
Main Functions 135
3.17 Wet Protection Control I
Outline When the outside air temperature is low, the lower limit of operating frequency is restricted to
ensure the compressor suction air humidity.
Details The lower limit of operating frequency (FCG) is set according to following formula and diagram
when the outside air temperature (DOA) is 6.5°C or lower during heating operation.
FCG = KCG1W ×outside air temp. (DOA) + FCG7W = 102/64 × (DOA) + 28
Outside Air Temp. Lower Limit of
Frequency
6 30
4 30
2 30
0 30
-2 32
-4 35
-6 38
-8 41
-10 44
-12 48
-14 51
-16 54
-18 57
-20 60
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
65.0
Operating frequency
-25 -20 -15 -10 -5 0 5 10
Outside air temp. 102/64 × Outside air temp.
(M1025)