Pioneer LISAS-B-1403, Service Manual

Page: 112 / 151

Electrical Control Function
110 Electrical Control System
1.3.3.4 Defrosting mode
：
For 12K-18K Units
Condition of defrosting:
----T4
＞
0
℃
,
Defrosting starts when either of the following
①
&
②
:
①
The units run with T3
＜
3
℃
for 40 minutes and T3 keeps lower than TCDI
℃
for more than 3 minutes.
② :The units run with T3 ＜ 3 ℃ for 80 minutes and T3 keeps lower than (TCDI+2) ℃ for more than 3 minutes..
----T4
＜
0
℃
,
If
①
and
②
are satisfied, then the program judges if T2 has decreased more than 5
℃
.When T2 has
decreased more than 5
℃
, enter the defrosting mode.
----No matter what value of the T4 is and whether the T2 drops more than 5 ℃ or not, if the machine runs
with T3
＜
3
℃
for more than 120 minutes and T3 keeps lower than (TCDI+4)
℃
for more than 3 minutes, the
machine will enter defrosting mode.
Condition of ending defrosting:
If any one of the following items is satisfied, the defrosting will finish and the machine will turn to normal
heating mode.
----T3 rises to be higher than TCDE1
℃
.
----T3 keeps to be higher than TCDE2
℃
for 80 seconds.
----The machine has run for 10 minutes in defrosting mode.
 Defrosting action
：
For 12K units ：
no longer than 10min
60s
on 10s F8 30s
Compressor F2 off
on on
4-way valve on
off off
Outdoor fan off
on on
Indoor fan off
breeze 10s