–24–
(3) Fan control
Controls the fan speed based on the piping temperature (TH1) to perform cooling at low outdoor temperatures and heating
at high outdoor temperatures.
1) Control at cooling
1
When the compressor stops, the fan stops (fan output = 0 %).
2
When the power is turned on, or when the compressor is restated after it has been stopped for 30 minutes or
longer, the piping temperature ( TH1) determines the fan output.
When TH
=
>
25
°
C
Fan output = 100 %
When TH < 25
°
C
Fan output = 60 %
3
When the compressor is restarted within 30 minutes after it has been stopped, the fan step before the compres-
sor was stopped is selected. However, when the fan output was under 30% when the fan was stopped, 30 % is
selected.
4
When the mode was changed from heating to cooling, the fan step conforms to item
2
.
5
Two minutes after the fan is started, the fan step (number of units) is controlled every 30 seconds based on the
piping temperature (TH1).
6
When TH1 reaches 50
°
C or higher, or when the control high pressure switch (63H2) tripped, the fan output
becomes 100 %.
7
Fan output while the compressor is operating is within the 20 % to 100 % range.
• FAN step
The following expression determines the next fan step count nj+1:
nj+1 = nj+
∆
nj
nj: Current fan step,
∆
nj: Displacement step amount
nj control
• If nj+1
=
>
100 %
nj+1 = 100 %
• If nj+1
=
<
20 %
nj+1 = 20 %
• If TH1
=
>
50
°
C or 63H2 is “OFF”
nj+1 = 100 %
FAN
∆
nj
Outputs are all %.
* In the night mode, the maximum value of nj is 80%. (When TH1 < 50
°
C)
Target condensation
temperature 31
°
C
Condensation temperature TH1
20
=
<
nj < 50
50
=
<
nj
=
<
100
Current
output
t > 49
°
C
5
10
t = 49
t > 46
3
4
~
~
~
~
~
~
~
~
~
t = 46
t > 43
2
3
t = 43
t > 40
2
2
t = 40
t > 36
2
2
t = 36
t > 33
2
2
t = 33
t > 29
0
0
t = 29
t > 26
–2
–2
t = 26
t > 23
–2
–2
t = 23
t > 20
–3
–4
t
=
<
20
°
C
–5
–10
