1
- 17
2WAY SYSTEM
Control Functions-Outdoor Unit
1
5. Outdoor Fan Control
2WAY SYSTEM
5. Outdoor Fan Control
5-1. No. of fan motor
No. of fan motor 1
1
1
1
1
1
2
2
Outdoor unit capacity 8HP 10HP 12HP 14HP 16HP 18HP 20HP
5-2. Fan mode
5-2-1. High Static Pressure Mode
The outdoor unit allows a high static pressure changing the settings.
The maximum permissible static pressure is 80Pa.
EEPROM setting in each outdoor unit
CODE : 8F
Setting No.
0
1
2 - 6
Invalid (factory preset mode)
High static pressure mode
Never use
These outdoor units utilize a DC fan motor that can be controlled in a maximum of 15 steps (15 modes).
However, fan modes 14 and 15 can only be used if high static pressure mode has been set.
* For information concerning EEPROM settings, refer to the field application functions.
The following table shows the maximum and minimum fan mode and fan forced mode for each unit.
Control Functions-Outdoor Unit
* For the sake of protecting temperature of the electrical parts, the minimum values of the fan mode may
sometimes increase in accordance with the ambient temperature.
Standard
>10°C
Ambient
temperature
>10°C
Ambient
temperature
<_10°C
Ambient
temperature
<_10°C
Ambient
temperature
Condenser
Evaporator
Condenser
Evaporator
Silent mode 1 (-3dBA)
Silent mode 2 (-5dBA)
Status of heat
exchanger
High static
pressure
mode
setting
Silent mode
Maximum
value
Minimum
value *
16hp
18hp
20hp
14hp
12hp
10hp
12
12
13
12
12
13
8
9
1
13
13
13
13
13
13
10
11
1
13
13
13
13
13
13
10
11
1
13
12
13
12
12
13
8
9
1
13
12
13
12
12
13
9
10
1
13
13
13
15
15
15
1
10
11
8hp
13
13
13
15
15
15
1
10
11
3WAY SYSTEM
Control Functions
5. Outdoor Fan Control
This control is intended to prevent snow from accumulating on stopped fans.
When the outdoor unit is stopped, the fan motor is forcibly started by the control for fan crack prevention’s fan
mode.
5-2-2. Snow Removal Control
(1) Independent control of outdoor unit
（
control for fan crack prevention
）
If a snow detection sensor (field supply) is available, the snowfall-protection hood might be unnecessary
excluding heavy snow region.
When set in this mode, the fan motor is forcibly started by the snowfall sensor control’s fan mode.
One snow detection sensor can control all outdoor units on the communications wiring.
The snow detection sensor must be connected to one of the main units (unit No.1) and it can control all outdoor
units in communication wiring.
(2) Control with snow detection sensor (Field supply)
Fan motor operates for 45 seconds and stops for 2 hours when ambient temperature is 5.1°C or more.
Fan motor operates for 45 seconds and stops for 1.5 hours when ambient temperature is 0.1 ~ 5.0°C.
Fan motor operates for 45 seconds and stops for 1 hour when ambient temperature is 0.0°C or less.
* To activate this function, it is necessary to set it to all EEPROMs on outdoor PCBs.
CODE: 04
Setting
No.
Operation
0
1
2
3
Snow detection sensor is NOT connected with this unit.
But this function is performed according to the signal of the sensor connected with other outdoor
unit.
(Factory preset mode)
Snow detection sensor is connected with this unit.
And this function is performed according to the sensor signal.
Snow detection sensor is NOT connected with this unit.
And this function is NOT performed.
Snow detection sensor is connected with this unit.
But this function is NOT performed.
System address 1
System address 2
System address 3
Unit No. 3
Unit No. 3
2
.
o
N
ti
n
U
2
.
o
N
ti
n
U
Unit No. 1
ON
ON
Fan motor state
in case of snow
ON
Unit No. 3
Unit No. 2
Unit No. 1
Unit No. 1
OFF
OFF
OFF
ON
ON
ON
2
0
2
0
2
0
0
0
1
* All main outdoor units are connected with same communication wiring.
Snow detection sensor
Setting No.
SM830204-05_2WAY SYS.indb 17
2015/01/21 17:00:01
Summary of Contents for U-20ME1E81
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