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⚙️ External Input & Output – AOTA90LALT Outdoor Unit

Overview

The Fujitsu AOTA90LALT Outdoor Unit includes multiple external input and output terminals that enable integration with external devices such as timers, building management systems (BMS), and heaters.

These terminals allow the system to respond to external commands and output operation or error signals for monitoring purposes.

1. Available External Terminals

2. External Input Functions

A. Low Noise Mode

This input reduces the operating sound level of the outdoor unit.
It can be enabled using a commercial ON/OFF switch connected to the outdoor control PCB (CN131).

How It Works

• ON: Low noise mode active

• OFF: Normal operation

• Performance may vary depending on ambient air temperature and system load.

Connection Overview

• Voltage: DC 5–24 V

• Current: Approx. 100 mA

• Recommended resistance:

  • 470 Ω for 5 V

  • 1 kΩ for 12 V

  • 2.2 kΩ for 24 V

• Maximum cable length: 10 m

Optional Part: UTY-XWZXZ2 (External input wire – Red/White/Black)

⚠️ Technician Tip:
Set the “Low Noise” level on the outdoor control PCB using the push switch after wiring completion.

B. Peak Cut Mode

This function reduces power draw by limiting compressor current.
It is activated in the same way as Low Noise Mode via external ON/OFF contact.

How It Works

• ON: Peak Cut Mode active (reduced current operation)

• OFF: Normal operation

Connection Details

• Connector: CN131

• Voltage: DC 5–24 V

• Rated current: 10 mA or more

• Distance: Within 10 m from control PCB

• Resistance:

  • 470 Ω (5 V), 1 kΩ (12 V), 2.2 kΩ (24 V)

Optional Part: UTY-XWZXZ2 (External input wire – Red/White/Black)

? Note:
Set the “Peak Cut Mode” operation level using the push switch on the outdoor control PCB.

3. External Output Functions

A. Error Status Output

Outputs an error signal when the air conditioner detects a fault.

Connection Details

• Connector: CN136

• Voltage: DC 24 V or less

• Load: 20 mA or less

• Maximum cable length: 10 m

Output Signal Behavior

Optional Part: UTY-XWZXZ2 (External output wire – Red/White/Black)

B. Compressor Status Output

Outputs a signal indicating compressor operation.

Connection Details

• Connector: CN136

• Voltage: DC 24 V or less

• Load: 20 mA or less

• Maximum cable length: 10 m

Output Signal Behavior

Optional Part: UTY-XWZXZ2 (External output wire – Red/White/Black)

4. Base Heater Output

The base heater output activates a heater element to prevent ice buildup on the outdoor unit base during low ambient conditions.

Connection Details

• Connector: CN115 (Black)

• Power Supply: AC 240 V

• Allowable Power: 25 W or less (direct connection)

• Temperature Control:

  • ON when ambient ≤ 2 °C

  • OFF when ambient ≥ 4 °C

When using a heater above 25 W:

• Use a contactor or relay circuit to handle higher load current.

Required Parts (Field Supply):

5. Wiring Summary

⚙️ Installation Tip:
Always insulate unused wires and secure them with insulation tape. Maintain a maximum 10 m cable run between the control PCB and connected devices.

6. Key Takeaways

• Enables external control and monitoring of outdoor unit functions.

• Each mode or output must be correctly wired and configured via control PCB push switches.

• Use only approved optional parts (UTY-XWZXZ2) and field-supplied connectors.

• Follow specified voltage, resistance, and wiring guidelines to avoid control errors or damage.

Support

For wiring diagrams, component sourcing, or control PCB configuration support:

• ? Fujitsu Assist Technical Support: 1300 364 484 or +64 4 568 8761 NZ

• ? technical.cupport@fujitsugeneral.com.au