Fujitsu UTY-TTRXZ1 Third Party Thermostat Convertor Setup with 24V Transformer

Fujitsu UTY-TTRXZ1 Third Party Thermostat Convertor Setup with 24V Transformer

Fujitsu UTY-TTRXZ1 (Replaces UTY-TTRX) is a Thermostat converter for high-efficiency Halcyon mini-split and Airstage variable refrigerant (VRF) heating and cooling systems.

It allows the Fujitsu system to be controlled by third-party thermostat such as Honeywell and Nest.

At the center of this connection is the converter which is connected to the PCB of the indoor unit. The wiring to the indoor unit and whether it requires 2 or 3 wires depends on the applications of the thermostat.

Setup Examples

Single-stage Cooling and Heating


Two-stage Cooling and Heating


Single-stage Cooling and Heating with Dedicated Fan Speed Relays




Other features to note:

  1. All wiring should be performed with 18 AWG thermostat wire
  2. Terminals to thermostat controller support 20-30VAC
  3. High/medium/low fan signals are optional and may not be available on all thermostat models
  4. W2 and Y2 signals are optional and may be omitted for single-stage thermostats. If Y2 and W2 are used, turn ON the DIP switches
A 24V isolation field transformer is also needed for the setup.

Before doing any installation, it is important to take note of the thermostat's voltage rating. The thermostats should not exceed the current capacity for the wires. If one is not trained to handle such electrical equipment, it is advisable to get a qualified technician to help in the set-up. This is key for safety.

Here are other HVAC Control Adapters.

For other custom HVAC control solutions, feel free to contact our HVAC Controls Engineering team for assistance.

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