Quick Summary
The HTW-31-F17-2IEN is a Modbus Thermostat with Sensor for indoor fan coil units in a 2-pipe, cooling-only HVAC system. It controls a 3-speed fan (on/off outputs) and provides a 0–10V valve output for cooling water flow regulation. The unit supports Modbus communication for system integration and allows internal or external temperature sensing configuration. Power failure memory helps restore the last operating status after power returns, supporting stable operation in daily use.
On this page, you will find the functional meaning in real FCU projects, a wiring reference for installation, key parameters for project confirmation, model code guidance for correct selection, OEM/ODM possibilities for supply, and common questions answered for deployment of a Modbus Thermostat with Sensor.
Key Functional Highlights
(This section explains the core control functions and their practical value.)
(1) Cooling-only control logic for 2-pipe FCU
This Modbus Thermostat with Sensor is built for 2-pipe cooling fan coil projects where control scope is clear. It supports consistent room cooling control without mixing heating requirements in the same terminal.
(2) Fan and valve coordination for stable commissioning
The thermostat manages a 3-speed fan using on/off outputs and provides a 0–10V signal for the valve. This helps installers tune cooling response and reduce frequent temperature swings in operation.
(3) Flexible sensing to match installation reality
A Modbus Thermostat with Sensor often faces different mounting positions on site. By allowing internal or external sensor configuration, the project team can choose a sensing method that fits the room layout and avoids biased readings.
(4) Power failure memory for operational continuity
In buildings with occasional power interruptions, the thermostat can restore the last state after power returns. This supports predictable behaviour and reduces repeated manual setting work for maintenance staff.
First Screen Overview
| Manufacturer | Swan Controls |
| Model | HTW-31-F17-2IEN |
| Fan Type | 3-speed fan |
| Valve Type | On/off output, 0–10V valve output |
| System Integration | Modbus; internal and external sensor configurable |
| Power Supply | 110–230 VAC |
| Customisation | OEM supported; ODM by discussion |
Display
Specifications
(Key parameters for reference and project confirmation.)
| Parameter | Value |
|---|---|
| Power Supply | 100–240 Vac |
| Frequency | 50/60 Hz |
| Accuracy | ±1°C (Step control by 0.5°C) |
| Setpoint Range | 10–30°C |
| Ambient | 0–50°C |
| Power Consumption | 1.5A |
| Protection Class | IP30 |
| Mounting | 86×86 mm standard junction box |
Wiring
(Provides the wiring reference diagram for correct installation.)
Guide
(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 |
| W | Wi-Fi |
| N | N for Modbus |
| K/E | K for Keycard; E for External sensor |
| Example HTW-31-F17-xx: if xx = 2E, it stands for a 3-speed fan, 2-pipe system with on/off valve control, external sensor function. Most sub-models are ready-made. Kindly contact us to confirm availability. | |
Project Fit & Customization
(This section explains where the product can be used, its limits, and OEM/ODM options.)
In a typical FCU room-control design, the HTW-31-F17-2IEN Modbus Thermostat with Sensor is suitable for 2-pipe cooling-only applications where the fan and valve need local control. It is not an ideal choice for projects that require complex multi-zone coordination, central time schedules enforced by a BMS across many terminals, or advanced energy strategies that must override local control at all times. In such cases, a higher-level controller or a different architecture may be required, because a room thermostat is designed to keep local comfort with a defined control scope.
Despite these limits mentioned above, we can support ODM functions customisation by discussion. For example, communication settings, parameter ranges, sensor selection behaviour, and control logic details can be reviewed with the project team based on the FCU type and site conditions. The goal is to align the Modbus Thermostat with Sensor behaviour with commissioning needs, while keeping the solution stable and maintainable for long-term operation.
OEM support is also available for project supply, including OEM logo printing, colour customisation, label changes and packaging adjustments. These options help distributors and integrators deliver a consistent product identity while keeping the same technical platform of a Modbus Thermostat with Sensor for their target market.
Certifications
Exhibition Moments
Frequently Asked Questions
Q1. Is this thermostat suitable for all FCU projects?
This Modbus Thermostat with Sensor is intended for 2-pipe cooling fan coil units. Please confirm fan wiring type, valve actuator signal, and site control requirements before selection.
Q2. Can it connect to a building management system?
Yes. The Modbus Thermostat with Sensor supports Modbus communication for monitoring and parameter access through compatible BMS or gateway devices, depending on your network design.(if you don’t need modbus, click here)
Q3. How do I decide between internal and external sensor?
Use the external sensor when the wall position is affected by drafts, sun, or equipment heat. Otherwise, internal sensing is often sufficient for standard rooms.
Q4. What is the MOQ and can I get samples?
Samples are supported for evaluation. The usual MOQ is 300 units, and smaller quantities can be discussed based on your project schedule and supply plan.
Q5. How can I place an order?
Please contact us with your requirements. After confirmation, we will provide a proforma invoice. Payment can be TT, PayPal, Visa, and more, with EXW, FOB, DAP and other terms.
Q6. How do you ship the goods?
We usually suggest express door-to-door service, around 7 days. Air freight is also about 7 days. Sea freight normally takes one month or longer, depending on route and season.
For 2-pipe cooling-only FCU projects, a Modbus Thermostat with Sensor should match the fan type, valve signal, sensing method, and BMS communication needs before selection. The HTW-31-F17-2IEN is suitable for projects that need 3-speed fan control, 0–10V valve output, internal or external temperature sensing, and stable Modbus integration. For OEM buyers, contractors, and system integrators, confirming wiring, sensor position, communication settings, and project quantity before ordering will help reduce commissioning issues.
Need Project Support?
If you are planning a fan coil project and need help selecting a Modbus Thermostat with Sensor, contact us with your system details. We can help confirm fit and configuration.
