Service manual


GB
Defrost of heating mode(figure 6)
1. Defrost start condition
If outdoor ambient is more than or equal to 61
O
F,it can’t defrost. When the time of defrost
interval is end , outdoor coil pipe temp. and outdoor ambient temp. continuous meet all
conditions for 5 minutes, it enter defrost process:
1) If outdoor ambient temp. less than or equal to 32
O
F , �hen T
pipe
≤0.8T
temp
+a
O
F( a is a
adjust constant ), it enter defrost process.
2) If outdoor ambient temp. more than 32
O
F and less than or equal to 59
O
F , �hen T
pipe
≤
0.2 T
temp
+a
O
F, it enter defrost process.
3) If outdoor temp. sensor is failure, �hen outdoor coil temp. T
pipe
≤+a
O
F, it enter defrost
process.
4) If coil temp. sensor of outdoor unit is failure, �hen defrost interval time is end, it enter
defrost, the time of defrost is four minutes.
5) During the first ten minutes of outdoor running in heating mode, the time is clear
and it judge �hether outdoor coil pipe temp. and outdoor ambient temp. satisfy
defrost condition, if the frequency of compressor is 25Hz and satisfy defrost condition,
then if enter defrost process. After end defrost process or over 10 minutes it return
normal running.
2. Defrost end condition
1) T
pipe
≥b
O
F(b is a adjust constant)or defrost time more than or equal to c minutes(c is a
adjust constant)it exit defrost process.
2) When outdoor coil pipe sensor is failure, defrost time is four minutes, it exit defrost process
after four minutes.
3. Interval time of defrost
1) Defrost interval time restriction: Max 120 minutes, Min 25 minutes.
2) The first frost interval time is 0 minute after heating.
3) The second defrost interval time is base on 60 minutes, it adjust according to belo�
table.
4) Form second time, defrost interval time adjustment as belo� table.
Interval time(td) Change
Td<minutes Last interval time add 5 minutes
3 minutes≥Td≥2 minutes Same as last interval time
≥4 minutes Last interval time reduce 5 minutes