Quick Summary
The T6861 digital thermostat (9-terminal version) is designed for fan coil unit systems in commercial spaces. It controls three-speed fans and on/off valves in both 2-pipe and 4-pipe systems. The unit supports heating and cooling modes based on system setup. It uses built-in sensing and optional inputs to keep the room temperature steady.
This page explains how the T6861 digital thermostat works in real FCU applications. It covers how the main functions help daily operation and system control. You will also find key parameters and typical project questions. Guidance is included to help choose the right model and options.
Key Features
(This section introduces the main control functions and their engineering value in the specific HVAC system.)
(01) 3-speed fan control
This room thermostat supports low, medium, and high fan speeds for flexible airflow control. This helps match room demand more closely, improving comfort while reducing energy use during light load conditions.
(02) 2/4 pipe valve control
Works with both 2-pipe and 4-pipe systems using simple on/off valves. This makes installation easier and avoids using different thermostats across mixed building systems.
(03) Remote setback or sensor input
Provides either keycard setback or remote sensor input, depending on the model. This helps save energy in empty rooms or improves temperature sensing in larger spaces.
This model is a 9-terminal version, so it can only support one of these two features. If both features are required, one may refer to this 12-terminal model instead (click → T6861).
(04) Timer on/off function
Allows the system to start or stop at set times during the day. This reduces manual operation and helps keep daily schedules consistent in offices or hotels.
(05) °C or °F selection
Offers both Celsius and Fahrenheit display options for easy use. This makes the thermostat suitable for projects in different regions without changing settings.
Product Design and Display
(This section shows the thermostat appearance, screen interface, or installation dimensions of this specific model.)
Technical Specifications
(This section lists the key technical parameters relevant to this room thermostat model.)
| Parameter | Value |
|---|---|
| Power Supply | 220Vac |
| Current Load | Fan relay 5A |
| Sensor Type | Built-in NTC3950, 10K |
| Temperature Accuracy | ±0.5°C |
| Setpoint Range | 10–32°C |
| Installation | 86×86 mm or US 2×4 box |
| Warranty | 2 years |
Wiring Diagram
(This section provides the wiring diagram for this thermostat in the relevant HVAC control system.)
Model Code Guide
(This section explains what configuration the model code refers to.)
| T6861 series | xx stands for |
| H | H=horizontal |
| 2 | 2=220V |
| W | White housing |
| G or B | G=green screen; B=blue screen |
| M or R | M=remote setback; R=remote sensor |
| Example T6861V2WG | Vertical type, 220V power supply, green screen |
Applications and Customisation Options
(This section describes project suitability, system limitations, and available customisation options.)
This room thermostat is not suitable for central control or BMS systems. It does not support Modbus, BACnet, or similar communication options. There is no WiFi or mobile app control available. It is also not designed for modulating valve control.
OEM support includes logo printing on the front panel and packaging. Housing colour may be adjusted based on project needs. Labels, manuals and packaging design can be adapted for different markets.
Certificates and Compliance
(This thermostat complies with European market requirements and is supported by certifications such as CE, RoHS, LVD test reports, EMC test reports, etc)
Exhibition Moments
(This section shows our participation in global HVAC exhibitions and industry events.)
Frequently Asked Questions
Q1: Can this room thermostat work with both 2-pipe and 4-pipe systems?
Yes, it supports both on/off valve control. The setup depends on how the system is wired on site.
Q2: Can I use a remote temperature sensor?
Yes, some versions support a remote sensor input. This is useful when wall temperature does not reflect the real room condition.
Q3: Does it support BMS connection?
No, it is a standalone thermostat without communication features. It is used for local room control only.
Q4: How does the keycard function work?
The thermostat reduces operation when the room is empty. This helps save energy in hotel or rental projects.
Q5: What is the MOQ and do you offer samples?
We support samples for testing. MOQ is usually 300 units, but smaller trial quantities can be discussed.
Q6: How do I place an order?
Contact us to confirm details and receive a PI. We accept TT, PayPal, and Visa, with EXW, FOB, or DAP terms.
Q7: How long does production take?
Non-custom samples are ready within 7 days. Custom orders take 3–5 weeks, and 300 units usually need about one month.
Q8: How will the products be shipped?
Courier delivery takes about 7 days door-to-door. Air is similar, while sea shipping usually takes about one month or more.
Need Help Choosing the Right Model?
If you are planning an FCU project, feel free to contact us. We can help check wiring, functions, and suitable options.
Related Thermostat Models
(just click it → ) Wi-Fi Thermostat | Modbus Thermostat | BACnet Thermostat
