FILE NO. SVM-10036
19
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-
7-4. High-Temperature Limit Control
7-6. Defrost Operation
The microcontroller detects the indoor heat exchanger
Dur
temperature to pre
ing the heating oper
v
ation, the outdoor heat
ent pressure of a refr
e
iger
xchanger temper
ating cycle
ature goes do
from increasing e
wn and sometimes it is
xcessiv
froz
ely
en.
.
In this case
The compressor and outdoor f
, the air conditioner stops the heating
an motor are controlled
oper
as sho
ation and star
wn in Fig.
ts the defrost oper
7-4-1.
ation to melt ice
Fig. 7-4-1
.
7-5.
7-6-1.
Lo
Condition to star
w-T
t the defr
emperature Limit Contr
ost operation
ol
The defrost oper
The microcontroller detects the indoor heat e
ation star
xchanger
ts whiche
temperature to pre
v
v
er belo
ent the indoor heat e
w
xchanger from
conditions are satisfied.
freezing.
(1)
The compressor and outdoor f
When the cum
an motor are controlled
ulativ
as sho
e compressor oper
wn in Fig.
ating time is
7-5-1
longer than 40 or 90 minutes and difference
betw
Fig. 7-5-1
een the indoor heat exchanger temperature
and the room temperature is less than the
specified value
60
.
(
(This value is decided b
°C)
y the
53
microprocessor
52
.) (Control example is shown in
Fig. 7-6-1. In case of B or C, the defrost operation
Compressor
starts
Outdoor fan
.)
OFF
(2)
OFF
When the current limit control or the high
ON
temperature limit control is perf
ON
or
OFF
med f
ON
or total of
90 min
Heat exchanger
utes
temp.
.
Fig. 7-6-1 (Indoor fan speed : M)
7-6-2.
5
Defr
(
ost operation time control
°C)
<In case of B>
2
(1) The heating operation is performed for at least
40 min
Compressor
utes
Outdoor fan
.
ON
(2)
Less than 2
The maximum defrost oper
°C continues
ating time is 6 min
for 5 minutes
utes
OFF
.
Heat exchanger
The defrost oper
temperature
ating time for the 4th cycle is
10 minutes. (When the outdoor temperature is
very low, however, the defrost operating time is
10 minutes.)
Indoor heat e
xchanger temp
- Room temp
Cumulative
compressor
operating time
D
B
C
A
Summary of Contents for 38NQ009N
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