Mitsubishi Heavy Industries V Multi FDC71VNX Technical Manual page 36

Operating temperature range
■ Cooling
50
43℃DB
40
30
20
10
0
-10
-20
10
■ Heating
30
25
20
15
10
5
-25 -20
Decline in cooling and heating capacity or operation stop may occur when the outdoor unit is installed in
places where natural wind can increase or decrease its design air flow rate.
"CAUTION" Cooling operation under low outdoor air temperature conditions
PAC models can be operated in cooling mode at low outdoor air temperature condition within above temperature range. However in
case of severely low temperature conditions if the following precaution is not observed, it may not be operated in spite of operable
temperature range mentioned above and cooling capacity may not be established under certain conditions.
[Precaution]
In case of severely low temperature condition
1) Install the outdoor unit at the place where strong wind cannot blow directly into the outdoor unit.
2) If there is no installation place where can prevent strong wind from directly blowing into the outdoor unit, mount the flex flow
adapter (prepared as option part) or like such devices onto the outdoor unit in order to divert the strong wind.
[Reason]
Under the low outdoor air temperature conditions of -5℃ or lower, the outdoor fan is controlled at lower or lowest speed by outdoor
fan control, but if strong wind directly blow into the outdoor unit, the outdoor heat exchanger temperature will drop more.
This makes high and low pressures to drop as well. This low pressure drop makes the indoor heat exchanger temperature to drop and
will activate anti-frost control at indoor heat exchanger at frequent intervals, that cooling operation may not be established for any
given time.
Usage range in cooling
-15℃DB
12 14 16
Indoor air temperature (℃WB)
Usage range in heating
-15 -10 -5
Outdoor air temperature (℃WB)
SRC40-60
46℃DB
18 20
0 5
35
- -
'19 • PAC-T-327
43℃DB
FDC71-140
22 24
10 15 20
PJG000Z014
26
25