Hi Power Mode; High-Temperature Limit Control; Low-Temperature Limit Control; Defrosting Operation - Toshiba RAS-18UFHP-ES Service Manual

7-3. Hi POWER Mode

([Hi POWER] button on the remote
control is pressed.)
When [Hi POWER] button is pressed while the indoor
unit is in Auto, Cooling or Heating operation, Hi
POWER mark is indicated on the display of the remote
control and the unit operates as follows.
(1) Automatic operation
• The indoor unit operates in according to the
current operation.
(2) Cooling operation
• The preset temperature drops 3°C.
(The value of the preset temperature on the
remote control does not change.)
• If the difference between the preset temperature
and the room temperature is big, the horizontal
louver moves to the Hi POWER position
automatically. Then when the difference
between them gets smaller, the horizontal
louver returns automatically.
• FAN speed : [AUTO]
If the difference between the preset temperature
and room temperature is big, the air conditioner
operates at maximum airflow level. If the
difference between the preset temperature and
the room temperature is small, the air
conditioner operates at normal airflow level.
• FAN speed : One of 5 levels
The air conditioner operates at normal airflow
level.
(3) Heating operation *Heating and Cooling Model
only
• The preset temperature increases 2°C,
(The value of the preset temperature on the
remote control does not change.)
• The indoor unit operates in normal heating
mode except the preset temperature is higher
(+2°C).
(4) The Hi POWER mode can not be set in Dry or Fan
only operation.

7-4. High-Temperature Limit Control

The microcontroller detects the indoor heat exchanger
temperature to prevent pressure of a refrigerating cycle
from increasing excessively.
The compressor and outdoor fan motor are controlled
as shown in Fig. 7-4-1.
Compressor Outdoor fan
OFF OFF
OFF
ON
ON
ON

7-5. Low-Temperature Limit Control

The microcontroller detects the indoor heat exchanger
temperature to prevent the indoor heat exchanger from
freezing.
The compressor and outdoor fan motor are controlled
as shown in Fig. 7-5-1
Heat exchanger
temperature
6
2

7-6. Defrosting Operation

*Heating and Cooling Model only
When the indoor unit is in heating operation, if the
refrigerant evaporation temperature detected by the
outdoor heat exchanger sensor is under the specified
temperature, the outdoor unit starts the defrosting
operation. At this time, the 4-way valve relay and the
outdoor fan motor are turned off. The indoor fan motor
is also turned off by the cold draft preventing control of
the indoor microcomputer. Then, [PRE. DEF.] lamp on
the indoor unit comes on.
The defrosting operation stops and the 4-way valve
relay, outdoor fan motor and the indoor fan motor are
turned on automatically when the refrigerant
evaporation increases to the specified temperature, or
when the defrosting time is over 12 minutes.
– 25 –
FILE NO. SVM-02009
Fig. 7-4-1
Compressor Outdoor fan
ON
Less than 2 continues
for 5 minutes
OFF
Fig. 7-5-1