28
Specifications subject to change without notice. 38MGR-04SM
Heating Mode
Fig. 33 — Heating Mode
Table 28 — Heating Mode
Table 29 — Heating Mode
NOTE: The final result is an integer.
Modify the result according to a T2 average (correction).
NOTE: Average value of T2; sum of T2 value of all indoor
units)/(indoor units number).
Fig. 34 — T2 Average
Use Table 30 and the final capacity request to confirm the operating
frequency.
Table 30 — T2 Average
The maximum running frequency is adjusted according to the outdoor
ambient temperature.
Fig. 35 — T2 Average
Defrosting Control
Defrosting Conditions
After the compressor starts and enters a normal operation, mark the
minimum value of T3 from the 10th to the 15th minute as T30.
If any one of the following conditions is satisfied, the unit enters the
Defrosting mode:
1. If the compressor’s cumulative running time reaches 29 minutes
and T3<TCDI1 and T3+T30SUBT3ONE
≦
T30.
2. If the compressor cumulative running time reaches 35 minutes and
T3< TCDI2 and T3+ T30SUBT3TWO
≦
T30.
3. If the compressor cumulative running time reaches 40 minutes and
T3<
24°C for 3 minutes.
4. If the compressor cumulative running time reaches 120 minutes and
T3<
15°C.
Defrost Stop Conditions
If any of the following conditions is satisfied, defrosting ends and the
unit returns to the normal heating mode:
....T3 rises above than TCDE1°C
....T3 remains at TCDE2°C or above for 80 seconds
....Unit runs for ten consecutive minutes in
DEFROSTING
mode
Defrosting Actions
Fig. 36 — Defrosting Action
Capacity Area
a
b
c
d
e
f
Norm code (N)
3
2
1.5
1
0.5
0
Model
9K
12K
18K
24K
HP
1.0
1.2
1.5
2.5
Frequency
(Hz)
0
HEAT_F1
HEAT_F2
...
...
HEAT_F24
HEAT_F25
Amendatory
Capacity
Demand
0
1
2
...
...
24
25
T1 Ts
4
0
a
3
1
ï
1
3
1
2
0
b
c
d
e
f
2
Decrease frequency
Keep frequency
Increase frequency
°C T2 average
47
40
n
o
ī
o
Cool-F9
10S 30S
TimeA
10S
compressor
Indoor fan
Outdoor fan
EXV open
frequency
Max 10 minutes
frequency
Compressor stops
o
ī
o
ī
s
0
4
2
r
o
f
P
0
8
4
P
0
8
4