1. Overview
The Low Noise Mode and Peak Cut Mode functions allow reduction of outdoor unit operating sound and power consumption, respectively.
These features can be activated using an external input signal (via connector CN131) or set directly from the outdoor unit PCB through function settings.
2. Required Component
External Connector Kit: UTY-XWZXZ2
(Includes red, white, and black lead wires for CN131 connection)
3. Function Description
| Function | Purpose | Operation |
|---|---|---|
| Low Noise Mode | Reduces compressor/fan speed to minimize operational noise | Activated via contact input signal (ON = low noise, OFF = normal) |
| Peak Cut Mode | Limits power draw and compressor capacity | Activated via contact input signal (ON = peak cut, OFF = normal) |
4. External Input Connection (CN131)
Connector: CN131 on outdoor PCB
Voltage: DC 5–24 V (100 mA max load)
Wiring distance: Up to 10 m from outdoor PCB
Circuit Example
Red: +V (5–24 V DC)
White: Signal (Switch input)
Black: GND
Switch Type
Use a toggle, rocker, or relay contact that can handle 10 mA DC current.
Typical resistor settings (for input current ≈ 10 mA):
5V DC → 470Ω
12V DC → 1kΩ
24V DC → 2.2kΩ
5. External Input Function
Low Noise Mode (CN131 Input)
ON: System enters low noise operation
OFF: System returns to normal operation
Noise level reduction is dependent on outdoor temperature and fan control logic.
Peak Cut Mode (CN131 Input)
ON: Limits compressor output to the defined percentage
OFF: Normal compressor operation resumes
6. External Output Options
Additional signals can be taken from other connectors if needed for monitoring:
| Output Type | Connector | Function |
|---|---|---|
| Error Status | CN136 | ON during fault condition |
| Compressor Status | CN136 | ON when compressor is running |
| Base Heater | CN115 | Active when outdoor temperature ≤ 2 °C |
Outputs are open-collector DC signals (24 V max, 20 mA).
7. Function Settings (Internal Configuration)
These parameters are adjusted through the Function Setting Mode on the outdoor unit PCB.
Access Procedure
Power ON the outdoor unit (system in standby).
Press MODE/EXIT once.
Press SELECT until F2 is shown on LED104.
Press ENTER to enter function mode.
Use SELECT to choose the setting item number.
Press ENTER to confirm and store.
8. Setting Codes
| Item | Setting Code | Factory Default | Available Options |
|---|---|---|---|
| Peak Cut Mode (Energy Saving Level) | 30 | 02 (Level 3 – 75%) | 00: Stop / 01: 50% / 02: 75% / 03: 100% |
| Low Noise Mode (Operation Setting) | 41 | 00 (Normal) | 00: Normal / 01: Low Noise Mode |
| Low Noise Mode (Operation Level) | 42 | 00 (Level 1) | 00: Level 1 / 01: Level 2 |
9. Setting Examples
To Enable Low Noise Mode:
Function Item: 41
Setting: 01
→ Outdoor unit reduces fan/compressor speed to minimize noise.
To Limit Output to 50% (Peak Cut Mode):
Function Item: 30
Setting: 01
→ Compressor output capped at approximately 50%.
10. Typical Installation Practice
Install the UTY-XWZXZ2 harness to CN131 on outdoor PCB.
Connect switch or BMS control relay for input.
Confirm wiring polarity and insulation.
Test by toggling input — verify operational response (fan speed/power change).
Store final configuration using the ENTER button.
11. Functional Verification
After setup:
For Low Noise Mode, system sound level should drop after 1–2 minutes.
For Peak Cut Mode, compressor current will reduce in line with the set level.
Both modes can be monitored via service LED indicators or current draw measurement.
12. Field Tips
Avoid setting both Low Noise and Peak Cut simultaneously unless required by site conditions (combined may limit performance).
Always restore factory defaults after testing to avoid unintended capacity limitation.
For long cable runs, use shielded wire to minimize interference on DC signal lines.
