--- title: "Gree U-Match Air Conditioning" description: "Gree U-Match R32 indoor units in TapHome via Modbus RTU over RS-485, one Gree Modbus Gateway per unit: power, mode, setpoint, fan, swing, temperature." url: "https://taphome.com/en/compatibility/gree-ac/" language: en lastmod: 2026-10-08 generator: hugo ai: topics: ["modbus-tcp","air-conditioning","hvac","rs-485","thermostat"] questions: ["How to integrate Gree U-Match air conditioning with TapHome?","What does the Gree AC TapHome template control and monitor?","How to connect Gree U-Match via Modbus to TapHome?","How to enable Modbus communication on a Gree indoor unit?","What fan speed levels are available for Gree U-Match in TapHome?","How to set the target temperature on Gree AC via TapHome?"] --- # Gree U-Match Air Conditioning Communication: Modbus TCP - [Gree Official Website](https://global.gree.com/) The Gree U-Match series are commercial/residential air conditioning units (duct-type, cassette, floor/ceiling) with R32 refrigerant. TapHome connects to each indoor unit via Modbus RTU over RS-485, using the Gree Modbus Gateway (TD GUD 30/01 or Mini ME30-24/E6) installed inside the indoor unit. The template provides power on/off control, operating mode selection (cooling, heating, drying, fan only, auto), thermostat setpoint adjustment, fan speed control (auto, 5 speeds, turbo), vertical and horizontal swing, and ambient/outdoor temperature monitoring. ## Enabling Modbus communication Before TapHome can communicate with the indoor unit, Modbus must be activated using the wired controller **XK117** (Z4K351GJ). ### Activating Modbus on the indoor unit 1. With the unit in **OFF** state, hold **FUNCTION** and **TIMER** buttons for more than 5 seconds to enter the settings menu ![Gree XK117 wired controller in OFF state — hold FUNCTION and TIMER to enter settings](https://taphome.com/images/compatibility/gree-ac/modbus-activation-step1_hu_3c40ff4a762edfaa.jpg) 2. Press **MODE** multiple times to reach the **10th settings parameter** (middle number), use the **arrow** buttons to select option **01** and confirm by pressing **SWING/ENTER** ![Gree XK117 wired controller — select 10th parameter value 01 and confirm with SWING/ENTER](https://taphome.com/images/compatibility/gree-ac/modbus-activation-step2_hu_af53921c16b47090.jpg) ### Setting the indoor unit address When multiple gateways share the same RS-485 bus, each indoor unit must have a **unique address**. Otherwise, keep the default address **1**. 1. With the unit in **OFF** state, hold **FUNCTION** and **MODE** buttons for more than 5 seconds ![Gree XK117 wired controller in OFF state — hold FUNCTION and MODE to enter address setting](https://taphome.com/images/compatibility/gree-ac/modbus-address-step1_hu_79c17119785d7e4f.jpg) 2. Use the **arrow** buttons to choose the unit address and confirm by pressing **SWING/ENTER** ![Gree XK117 wired controller — select unit address and confirm with SWING/ENTER](https://taphome.com/images/compatibility/gree-ac/modbus-address-step2_hu_87469fa2ac1a776.jpg) ## Hardware connection Each indoor unit requires its own Modbus Gateway module. The gateway connects to the indoor unit mainboard via the included 6-pin communication cable and provides an RS-485 interface for the Modbus bus. ### Gateway to indoor unit 1. Plug the 6-pin communication cable into the **brownish red** socket labeled **COM-BMS** (connector 9) on the indoor unit mainboard ![Gree duct-type indoor unit mainboard — COM-BMS socket location for Modbus Gateway connection](https://taphome.com/images/compatibility/gree-ac/pcb-mainboard_hu_1396ae18f326d78d.jpg) 2. Connect the other end to the Modbus Gateway socket labeled **UNIT** ![Gree Modbus Gateway (Mini) module — UNIT socket and RS-485 terminals (A, B, GND)](https://taphome.com/images/compatibility/gree-ac/gateway-module_hu_570a3c6471c03edf.jpg) ### RS-485 bus wiring Connect TapHome Core to the gateway's RS-485 terminals: | Terminal | Function | |----------|----------| | **A** | RS-485 Data+ | | **B** | RS-485 Data- | | **GND** | Signal ground | One twisted pair connects A and B, the remaining line(s) connect GND. ![RS-485 twisted pair wiring to A+, B- and GND terminals on Gree Modbus Gateway](https://taphome.com/images/compatibility/gree-ac/rs485-bus-topology_hu_b6eb4fb9e154233a.jpg) - **Cable:** Shielded twisted pair, 0.2-0.32 mm² (24-22 AWG), EIA-485 compliant (e.g. Belden 3016A) - **Topology:** Bus (daisy-chain) only — star, ring, or triangle connections are not supported - **Max length:** 500 meters - **Termination:** 120 ohm resistor between A and B on the first and last device on the bus - **Shielding:** Attach cable shield to chassis ground on **one** end only (preferably the outermost indoor unit) ![RS-485 daisy-chain bus topology with shielding grounded on one end](https://taphome.com/images/compatibility/gree-ac/rs485-shielding_hu_75d016efa9f96ec1.jpg) > [!WARNING] > The RS-485 bus must use a bus (daisy-chain) topology. Star, ring or triangle wiring will cause communication failures. ## Configuration - **Protocol:** Modbus RTU (wrapped in Modbus TCP by TapHome) - **Baud rate:** 9,600 bit/s - **Data bits:** 8, parity: none, stop bits: 1 - **Default Slave ID:** 1 When importing the template in TapHome, provide: - **IP Address** — the TapHome Modbus TCP gateway address - **Slave ID** — Modbus slave address of the indoor unit (default: 1) > [!TIP] > When controlling multiple indoor units, each gateway must have a unique slave address. Set the address via the wired controller before connecting to the bus. ## Device capabilities The template exposes the following devices: ### Power control - **Power On/Off** — switch to turn the air conditioning unit on or off. Uses register H:2 with non-standard values: 0xAA = ON, 0x55 = OFF. ### Operating mode - **Mode (multi-value switch)** — select from: Cooling, Heating, Drying, Fan Only, Auto. Uses register H:17 (UInt16). The available modes depend on the outdoor unit's capabilities — for example, if the outdoor unit supports cooling only, heating modes will be ineffective. ### Thermostat - **Thermostat** — reads indoor ambient temperature from register H:4 (value / 10) and reads/writes the desired temperature setpoint at register H:20. Range: 16–30 °C. ### Fan speed - **Fan Speed (multi-value switch)** — set fan speed via register H:19: Auto, Speed 1–5, or Turbo. Under drying mode, low fan speed is compulsory. Turbo is available in cooling/heating modes only. ### Swing control - **Swing Vertically** — toggle up-down swing on/off via register H:22. The service action "Set up & down swing" provides finer 12-position control (0–11). - **Swing Horizontally** — toggle left-right swing on/off via register H:23. The service action "Set left & right swing" provides finer 9-position control (0–8). ### Temperature monitoring | Register | Sensor | Description | In template | |----------|--------|-------------|-------------| | H:4 | Indoor ambient | Room temperature (value / 10) | Yes | | H:49 | Outdoor | Outdoor temperature (sign-bit encoded) | Yes | | Word 115 | Air outlet | Supply air temperature (value + 100 offset) | No | ### Service attributes The template also exposes diagnostic attributes readable in TapHome's service view: | Attribute | Register | Description | |-----------|----------|-------------| | IDU Addr. | H:5 | Indoor unit address on the gateway bus | | Fresh air valve status | H:24 | Fresh air valve open/close | | Sleep mode | H:25 | Sleep mode status (0=off, 1=on) | | Contamination grade | H:34 | Filter contamination level | | Selection of ambient temp sensor | H:39 | Active ambient temperature sensor | | DRED function | H:77 | Demand response enabling device status | | Ambient temp at the port of air return | H:82 | Temperature at the air return port | | Ambient temp of light board | H:83 | Light board temperature sensor | ### Additional capabilities The Gree Modbus protocol also exposes registers for energy saving limits (cooling/heating/dehumidifying temperature bounds), quiet mode, sleep mode, 8°C heating (absence mode), X-Fan, and filter cleaning reset. These can be added to the TapHome template in a future update. ## Troubleshooting ### No Modbus communication 1. Verify that Modbus communication was activated on the indoor unit via the wired controller XK117 (10th parameter set to 01) 2. Check the RS-485 wiring: A, B and GND terminals must be connected correctly 3. Confirm the baud rate is set to 9,600 in TapHome 4. Ensure the slave ID in TapHome matches the address configured on the indoor unit ### Mode changes not applied The outdoor unit's operating mode takes priority. If the outdoor unit supports cooling only, setting heating mode via Modbus will be ineffective. Error code 0x04 indicates a communication failure between the gateway and the indoor unit — check the 6-pin cable connection to the COM-BMS socket. ### Temperature setpoint ignored When the energy saving function is enabled, temperature commands outside the configured limits will be rejected. Verify the energy saving temperature bounds (Word 106–108) or disable energy saving via the indoor unit's controls. ## Available devices Gree U-Match AC Module Service Attributes | | | |----------------------------------------|----------------------------------------------------------------------------| | IDU Addr. | indoor unit address on the gateway bus | | Fresh air valve status | fresh air valve open/close status | | Sleep mode | sleep mode status; 0=off, 1=on (protocol Bit 301) | | Contamination grade | filter contamination grade | | Selection of ambient temp sensor | which ambient temperature sensor is active | | DRED function | demand response enabling device (DRED) function status | | Ambient temp at the port of air return | return air temperature; value multiplied by 10 in script (raw x10) | | Ambient temp of light board | light board temperature sensor; value multiplied by 10 in script (raw x10) | | Up & down swing | up-down swing position readback (multi-value); mirrors device #7 | | Left & right swing | left-right swing position readback (multi-value); mirrors device #6 | Service Actions | | | |------------------------|--------------------------------------------------------------------------------------------------------------| | Set up & down swing | set vertical swing to specific position; parameter \\'val\\' 0–11 maps to binary position codes (0000–1011) | | Set left & right swing | set horizontal swing to specific position; parameter \\'val\\' 0–8 maps to binary position codes (0000–1101) | Ambient Temperature Temperature Sensor Read-only Indoor room temperature — value divided by 10 Register: H:4 UInt16 Unit: °C numeric Fan Speed Multi-value Switch Fan speed selector — Auto, Speed 1–5, Turbo Register: H:19 UInt16 numeric Values / States: Auto · Speed 1 · Speed 2 · Speed 3 · Speed 4 · Speed 5 · Turbo Mode Multi-value Switch Operating mode selector — Cooling, Heating, Drying, Fan Only, Auto Register: H:17 UInt16 numeric Values / States: Cooling · Cooling · Heating · Drying · Fan Only · Auto Outdoor Temperature Temperature Sensor Read-only Outdoor ambient temperature with sign-bit encoding Register: H:49 Int16 Unit: °C numeric Power On/Off Switch Unit power switch — 0xAA=ON, 0x55=OFF Register: H:2 UInt16 numeric Values / States: ON · OFF Thermostat Thermostat Temperature setpoint 16–30 °C with indoor ambient reading Register: H:4 (current), H:20 (desired) → H:20 UInt16 Unit: °C numeric Swing Horizontally Switch Left-right air swing toggle — service action for 9-position control Register: H:23 Int16 numeric Values / States: SWING · OFF Swing Vertically Switch Up-down air swing toggle — service action for 12-position control Register: H:22 Int16 numeric Values / States: SWING · OFF **Connection:** Modbus TCP • Slave ID: $\[SlaveId] Possible improvements (14) - Word 106 Lower Limit Temp of Cooling Energy Saving — UInt16, value x10, range 16.0–30.0°C, R/W - Word 107 Upper Limit Temp of Heating Energy Saving — UInt16, value x10, range 16.0–30.0°C, R/W - Word 108 Lower Limit Temp of Dehumidifying Energy Saving — UInt16, value x10, range 16.0–30.0°C, R/W - Word 115 Air Outlet Temperature — UInt16, value + 100, range -30 to 138°C, read-only - Word 117 Gate Control Status — UInt16, 0=invalid, 1=without, 2=insert card, 3=disconnect card - Word 119 Category of Indoor Unit Model — UInt16, 1=Duct, 2=Cassette, 3=Wall, 4=Floor ceiling, etc. - Word 123 Rated Capacity of Indoor Unit — UInt16, hectowatt, read-only - Bit 296 Energy Saving — Coil, 0=off, 1=on, R/W - Bit 300 Dry Mode — Coil, 0=off, 1=on, R/W - Bit 301 Sleep Mode (coil) — Coil, 0=off, 1=on, R/W — currently read-only via service attribute - Bit 302 Quiet Mode — Coil, 0=off, 1=on, R/W - Bit 303 Ventilation — Coil, 0=off, 1=on, R/W - Bit 308 8°C Heating Function — Coil, 0=cancel, 1=start, R/W - Word 3302 Upper Limit Capacity of Outdoor Unit — UInt16, 30–100%, R/W, system-level ## Sources - Modbus Gateway (TD GUD 30/01) Installation Manual for U-Match R32 [www.gree.at](https://www.gree.at/uploads/navody/modbus_gateway_en.pdf) 2026-03-20 [PDF](https://taphome.com/compatibility/devices/gree-ac/manufacturer/modbus-gateway-installation-manual.pdf) - Gree Modbus Gateway(Mini) Communication Protocol V2.0 [www.asami.lt](https://www.asami.lt/uploads/Products/product_78/me30-24_e6-m-_mini_modbus_variable_list_en_1708354351.pdf) 2026-03-20 [PDF](https://taphome.com/compatibility/devices/gree-ac/manufacturer/mini-modbus-variable-list.pdf) ## Related Documentation - [Modbus Integration](https://taphome.com/en/compatibility/modbus-guide/) - [Modbus](https://taphome.com/en/docs/integration/modbus/) - [Simple configuration using templates](https://taphome.com/en/docs/integration/modbus/templates/) - [Modbus scripts and prefetch](https://taphome.com/en/docs/script/modbus-scripts/) - [Modbus functions](https://taphome.com/en/docs/script/modbus/) - [Modbus data types](https://taphome.com/en/docs/script/modbus-data-types/)