Panasonic U-120ME2U9 Service Manual page 27

5. Outdoor Unit Fan Control
5. Outdoor Unit Fan Control
1-2. Snow removal control
(1) Independent control of outdoor unit
This control is intended to prevent snow from accumulating on stopped fans.
The fan motor rotates at 500rpm in the below conditions even if the outdoor unit stops.
Fan motor operates for 45 seconds and stops for 2 hours when ambient temperature is 41.18°F (5.1°C) or
more.
Fan motor operates for 45 seconds and stops for 1.5 hours when ambient temperature is 32.2 - 41.0°F
(0.1 - 5.0°C).
Fan motor operates for 45 seconds and stops for 1 hour when ambient temperature is 32.0°F (0.0°C) or less.
(2) Control with snow detection sensor (field supply)
If a snow detection sensor (field supply) is available and this function is set in validity, the fan motor of the outdoor
unit rotates at 600 rpm when the snow detection sensor detects snow.
The judgment of this control performs at 10 minutes interval.
One snow detection sensor can control all outdoor units on the communications wiring.
The snow detection sensor is only possible to connect to the main outdoor unit (unit No.1) and it can control all
outdoor units in communication wiring.
To activate this function, it is necessary to set it to the EEPROM on each system's main outdoor unit PCB.
EEPROM setting in each main outdoor unit
CODE: 04
Setting No.
0 No snow detection sensor is connected but control is available. (at factory shipment)
1 Snow detection sensor is connected and control is available.
2 No snow detection sensor is connected and control is not available.
3 Snow detection sensor is connected but control is not available.
System address 1
Snow detection sensor installed
Setting No. 1
Fan motor
status during ON
snowfall
* All outdoor units are connected with same communication wiring.
System address 2
0 0 0
ON ON ON
1 - 19
Function
0 0 2
ON ON OFF
2WAY VRF SYSTEM
2WAY VRF SYSTEM
Control Functions
Control Functions
System address 3
2 2
OFF OFF
1
2
3
4
5
6
7
8
9