8921RHKLD-WIFI FCU & Floor Heating Thermostat

Key Specifications

· Integrated AC & floor heating thermostat for fan coil unit (FCU) and hydronic floor heating (water system)
· WiFi MI App available · RS485 connecting interface
· Four-chip design · Linkage function available
· Rumble motor inside
· 86×86×40mm · 210g

Why Choose 8921RHKLD-WIFI

· WiFi MI App – Remote control via Mi Home (MI) App for smart scheduling and operation
· RS485 Modbus – Built-in RS485 interface for building automation and central control
· Four-Chip Design – Enhanced processing stability and reliability
· Linkage Function – Optional device-to-device automation (e.g., with fresh air or curtains)
· Rumble Motor – Built-in vibration/haptic motor for tactile feedback (e.g., button confirmation)
· Compact Size – 86×86×40mm fits standard wall boxes
· Sturdy Build – 210g for reliable quality

Operation Functions


1. Basic Operation Modes
– Power On/Off: One-key control to turn the thermostat on or off.
– Cooling Mode: Provides cooling and controls the cooling valve.
– Heating Mode: Provides heating and controls the heating valve.
– Fan Mode: Runs fan only without cooling or heating.
– Fan Speed: Adjustable to Low, Medium, High, and Auto.

2. Temperature Adjustment
– Manually set desired temperature between 5°C and 35°C.
– High precision temperature control with ±1°C accuracy.

3. Child Lock & Timer Function
– Child Lock: Prevents misoperation by children.
– Timer: Supports 3-period cycle timer for auto on/off control.

4. Sleep Mode
– Automatically adjusts temperature for comfortable sleeping.
– Runs for 8 hours then exits automatically, saving energy.

5. Time Setting
– Allows manual time adjustment.
– WiFi version syncs time automatically from the internet.

6. Temperature Calibration
– Calibrates temperature display for accurate reading.

7. Power Failure Memory
– Restores previous settings automatically after power recovery.

8. Anti-Freezing Protection (Optional)
– Activates output automatically at low temperature to prevent freezing.

9. Fault Alarm
– Shows E1 code and stops output when sensor error occurs.

10. Factory Reset
– Restores all parameters to default settings.

11. Advanced Settings
– System type, temperature limits, fan control, backlight, and more customizable parameters.