7-2. Protective Functions
NOTE The numerical values such as temperature, frequency, time and current in parentheses are an example
of
7-2-1. Defrost Detection and Release
(1)
Defrosting sequence
Heating operation
Frost detection
Defrost detection occurs in either of the following cases:
The temperature of the heat exchanger remains at or below the L1 line for 35 minutes after the start of HEAT operation. The temperature of the heat exchanger remains at or below the L2 line for 120 minutes after the start of HEAT operation.
Outdoor heat
exchanger temperature (°F)
(- 4) | 0 | Outdoor air | |
temperature (°F) | |||
|
| ||
|
| ( 21.2) | |
L2 |
| ( 19.4) | |
| |||
L1 |
|
Releasing of defrosting
| Compressor |
| (80 Hz) operation |
|
| ||
| Outdoor fan |
| OFF |
|
| ||
|
| ||
| Solenoid valve |
| ON |
|
| ||
| (for hot gas bypass) |
|
|
| Indoor fan |
| OFF |
|
| ||
|
|
|
|
Temperature of the outdoor heat exchanger is at or above the temperature shown in the table below.
Defrost operation has continued for 12 minutes (max. length).
Temperature of releasing
Defrost operation time | Less than 2 minutes | 2 minutes or more |
|
|
|
Heat exchanger | No releasing | 57.2 °F or higher (*1) |
temperature for | ||
releasing defrosting |
|
|
|
|
|
*1 The temperature for releasing of defrosting is (68 °F) or higher when the outdoor air temperature is less than 32 °F.
NOTE Defrost does not occur during HIGH POWER operation.
If other stopped indoor units are started during defrost operation, they begin operating in defrost mode.
(2) Clean defrost
If all indoor units are stopped during HEAT operation, and frost is detected at the L1 line, and the conditions for defrost are met, then defrost operation occurs, and the unit stops after defrost is completed.
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