9-2. Protective Functions
■Overload prevention during heating
During HEAT operation, the temperature of the indoor heat exchanger is used to control the frequency and lessen the load on the compressor before the protective device is activated.
Indoor heat exchanger temperature (°C) | Approx. |
| A | Indoor heat exchanger | |
| A. Control start | ||||
53 |
|
| |||
|
| B. Control end | |||
|
|
| |||
Approx. |
|
|
| B | |
47 |
|
|
|
| |
| a | b | c | d | |
aArea: Automatic capacity control
bWhen Point A has been exceeded, the operation frequency is reduced by a certain proportion.
cArea: Frequency increase is prohibited.
dAt Point B and below, overload prevention is ended and control is the same as in the a area.
■Freeze prevention
During COOL or DRY operation, freezing is detected and operation is stopped when the temperature of the indoor heat exchanger matches the conditions below.
1
2Restart after
Indoor heat exchanger temperature (°C) | 8 |
|
| C |
|
|
| ||
6 | A | B |
| |
|
|
| ||
2 |
|
|
| |
* |
|
|
| |
| a | b | c | d |
aArea: Automatic capacity control
bWhen the temperature drops below Point A, the operation frequency is reduced by a certain proportion.
cArea: Frequency increase is prohibited.
dWhen the temperature reaches Point C or above, freezing prevention is ended and control is the same as in the a area.
*When the temperature drops to below 2°C (continuously for 2 minutes or longer), the compressor stops.
Once the freeze condition is detected, the air conditioner will work less than the maximum frequency until it is turned off.
■Cold-air prevention during heating
During heating, the fan speed is set to “LL” (very low) or stopped. As the temperature of the indoor heat exchanger rises, the fan speed is changed to the set speed.
High |
|
| Set fan speed |
|
|
| |
| Normal operation |
| |
|
|
| At start of operation |
LL |
|
|
|
Stopped | 25 | 30 | Approx. 40 |
| |||
Indoor heat exchanger
temperature (°C)
NOTE
•The fan speed is forcibly changed to “LL” beginning 30 seconds after the thermostat turns OFF.
•Normal operation refers to operation when the room temperature has approached the set temperature.
•When HEAT operation starts, the indoor fan is stopped until the temperature of the indoor heat exchanger reaches 20°C or higher, or until the room temperature reaches 15°C or higher.
■Compressor discharge temperature control
This function controls the operation frequency to prevent the compressor discharge temperature from rising more than a specified temperature.
Compressor discharge temperature (°C)
Approx. | A |
|
|
101 |
|
|
|
Approx. |
|
| B |
94 |
|
|
|
a | b | c | d |
aArea: Automatic capacity control.
bWhen the temperature rises above Point A, the operation frequency is reduced at a specified rate.
cArea: Further frequency increase is prohibited.
dWhen the temperature falls below Point B, prevention of a rise in frequency is released and the air conditioner operates as in a area.
*The compressor will stop if the temperature of the compressor discharge exceeds 120°C due to shortage of gas or other reason.
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