Quick Summary
The HTW-31-F10-4N digital thermostat is designed for fan coil unit systems, offering control of a 3-speed fan and on/off valves. It supports both 2-pipe and 4-pipe systems and ensures stable performance in both heating and cooling modes. RS485 Modbus communication is also supported.
This page explains how this digital thermostat works in real projects. It helps clarify control logic, wiring, and key parameters. It also covers common questions and model choices. Some custom options may be discussed based on project needs.
Key Functional Highlights
(This section introduces the main control functions and their engineering value in the fan coil HVAC system.)
(01) 3-speed fan control
This digital thermostat controls low, medium, and high fan speeds. It helps match airflow to room demand. This improves comfort and reduces energy waste. It also supports stable fan operation in daily use.
(02) 2/4 pipe on/off valve control (configurable)
The thermostat supports both 2-pipe and 4-pipe systems. It controls heating and cooling valves separately when needed. This gives flexible use across different projects. It also simplifies system setup during installation.
(03) RS485 Modbus
With Modbus communication, this thermostat connects to a BMS (building management system), which allows central monitoring and control. This is useful in hotels or office buildings. It helps reduce manual checks and improves system management.
BACnet models with the same design are also available in this series. If one prefers BACnet communication to Modbus, please refer to this model (please click → HTW-31-F10-2B/4B).
(04) Keylock function
The keylock function prevents unwanted changes to the thermostat and helps avoid incorrect settings in public spaces. This is useful in hotels, offices, or shared areas as it can improve system stability and reduce maintenance work.
(05) Set-point limitation
The set-point limitation function controls the allowed temperature range. It helps avoid extreme heating or cooling settings. It supports energy saving and keeps system operation within a safe range.
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 thermostat model.)
| Parameter | Value |
|---|---|
| Power Supply | 230Vac, 50/60Hz |
| Fan Relay Load | 5A |
| Sensor | NTC3950, 10K |
| Temperature Accuracy | ±0.5°C |
| Set-Point Range | 5~35°C |
| Installation | 86×86 mm or EU round 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.)
| Fan coil series | xx stands for |
| 2/4 | 2 for 2-pipe on/off; 4 for 4-pipe on/off system |
| M | Modulating valve control |
| W | Wi-Fi |
| N/B | N for Modbus; B for BACnet |
| K/E | K for Keycard; E for External sensor |
| Example HTW-WF11-FC-xx: if xx = 2EN, it stands for a 3-speed fan, 2-pipe system with on/off valve control, external sensor function, and Modbus communication. Most sub-models are ready-made. Kindly contact us to confirm availability. | |
Project Fit & Customization
(This section describes project suitability, system limitations, and available customization options.)
This digital thermostat is not suitable for EC fan systems. It does not support 0–10V control. It is also not ideal for projects needing BACnet. For advanced BMS or smart control, other models may be needed.
Despite these limits, some functions can be adjusted if discussed early. For example, communication options may be changed. External sensors or control logic can also be added. Final options depend on project details and volume.
We also support OEM requests for brand projects. Logo printing and label changes are available. Housing colour can also be customised. This helps match different project styles or market needs.
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
(Our team regularly participates in international HVAC exhibitions such as Febrava in Brazil, The Big 5 in Dubai, and ISK-SODEX in Turkey, etc.)
Frequently Asked Questions
Q1: Can this digital thermostat work with both 2-pipe and 4-pipe systems?
Yes, it supports both system types. The configuration can be set during installation. This makes it suitable for different project layouts.
Q2: Can it connect to a BMS system?
Yes, it supports RS485 Modbus communication. It can be integrated into a BMS. This allows central monitoring and control.
Q3: Does it support an external sensor?
This model uses a built-in sensor as standard. External sensor support is not included by default. It may be discussed for special projects.
Q4: Is it suitable for hotel or office use?
Yes, it works well in shared spaces. The keylock function helps prevent misuse. This improves system stability in daily operation.
Q5: What is the MOQ and can we get samples?
We support sample orders for testing. Standard MOQ is 300 units. Smaller quantities like 100 units can be discussed.
Q6: How do we place an order and arrange shipment?
Contact us to confirm your requirements. We will provide a PI. Payment supports TT, PayPal, and Visa. Terms include EXW, FOB, and DAP.
Q7: How long does production take?
Standard samples ship within 7 days. Custom orders need evaluation and adjustment. It usually takes 3–5 weeks. Bulk orders of 300 units take about one month.
Q8: What shipping options are available?
Courier delivery takes about 7 days door to door. Air freight is also around 7 days. Sea shipping takes about one month depending on destination.
Need Help Choosing the Right Model?
If you are unsure which digital thermostat fits your project, please feel free to get in touch with us. We can help review your system and suggest a suitable model.
Related Thermostat Models
For more details, please click here directly: Wi-Fi Thermostats | Modbus Thermostats | BACnet Thermostats
Final Note
In many HVAC projects, stable room control and easy management are key goals. This digital thermostat manages fan and valve operation with Modbus support. It helps improve system stability, supports central monitoring, and reduces manual work in daily facility management.
