Filter
Top Products
1
8-1. Fan mode
*
8-3. Fixed Initial Fan Mode
For the first 30 seconds after operation starts, the mode is fixed at the initial mode which was calculated from the
relationship between the outdoor air temperature and the outdoor unit horsepower.
If the outdoor unit horsepower changes dramatically, say for about 2 hp, the initial mode may be recalculated and
may be again fixed for 30 seconds.
8-4. Operation after Fixed Initial Fan Mode
(A) Fan mode is increased when the high pressure satulation temperature sensed by the pressure sensor is
high, and is decreased when the pressure sensor temperature is low.
(B)
(A)
(B)
(C)
(1)
(2)
*
1
14
14
These outdoor units utilize a DC fan motor that can be controlled in a maximum of 16 steps (16 modes).
However, fan modes 15 and 16 can only be used if high static-pressure mode has been set.
* For information concerning EEPROM settings, refer to the field application functions.
8-2. Outdoor Fan Min. Fan Mode and Max. Fan Mode
Min. fan mode
Max. fan mode
Cooling operation
Heating operation
Outdoor air temp. > 59
°F
: 1
Outdoor air temp.
<
59
°F
: 0
After the fixed initial fan mode, the fan mode is increased or decreased according to the operating conditions.
If the condensation temperature is low, the fan mode is increased at regular intervals.
If the condensation temperature is high, the fan mode is decreased in order to prevent excessive loads.
(1) When all indoor units are operating in cooling mode
The fan mode may be decreased when symptoms of insufficient refrigerant gas are detected at an indoor unit.
(2) When all indoor units are operating in heating mode
The fan mode may be increased when the outdoor liquid temperature drops to 44°F or below.
8-5. Snow Removal Control
When the outdoor air temperature is 50°F or below, the fan operates for 30 seconds every 2 hours in fan mode
8, even when the outdoor unit is stopped or the heat exchanger is not in use. This control is intended to prevent
snow from accumulating on stopped fans. (Because the outdoor air temperature cannot be accurately detected
when the unit is stopped, a higher outdoor air temperature is used for the control condition, in order to ensure
correct operation.)
If the fan mode becomes 0 during cooling operation, the fan mode is changed to 1.
This control is predictive control. Use a snowfall sensor as necessary according to the installation conditions.
8-6. When the Compressor Magnet Switch Seizing Alarm Occurs
Because there is the possibility that the high pressure has increased, the fan operates in Max. fan mode.
8-7. Other
This unit includes settings for high static-pressure and for Quiet mode.
For information about these settings, refer to the field application functions.
* The fan mode is always increased when the high pressure satulation temperature sensed by the pressure
sensor is 113°F or higher.
Even if the fan mode is 0 during cooling operation, the fan mode may change to 1 at regular intervals for tem-
perature protection of the inverter hybrid IC.
1 - 19
W-2WAY ECO-i SYSTEM
Control Functions
8. Outdoor Fan Control