Quick Summary
Smart Rs485 Modbus Thermostat HTW-WF81-863S is designed for indoor fan coil unit systems in residential and light commercial spaces. It controls a three-speed fan with separate heating and cooling valves. The unit supports four-pipe systems using simple on/off control logic. RS485 Modbus allows connection to building control systems.
This Smart Rs485 Modbus Thermostat is used in projects that need stable room control and central monitoring. The page explains key functions, control logic, and main parameters in a clear way. It also helps users match the thermostat with system needs. Common questions and custom options are included for reference.
Key Features
These functions support stable operation and practical use in four-pipe fan coil systems.
(01) RS485 Modbus communication
Modbus allows connection to BMS systems for central monitoring. It supports data exchange between devices. This Smart Rs485 Modbus Thermostat helps improve system control and management.
(02) 3-speed fan and dual valve control
Three fan speeds allow simple airflow adjustment. Separate outputs control heating and cooling valves. This matches standard four-pipe fan coil systems.
(03) Programmable scheduling
Weekly scheduling allows automatic temperature control during different periods. This helps reduce energy use when rooms are empty. It also keeps indoor comfort stable.
(04) Multi-language interface
Multiple language options make operation easy for users. This supports use in different regions. It also reduces training time after installation.
(05) WiFi support
WiFi allows remote access through a mobile app. The Smart Rs485 Modbus Thermostat supports flexible use when needed. It improves convenience in daily operation.
Product Design and Display
The design is simple and clean for indoor use. The screen is clear and easy to read. It fits standard wall boxes and common installation conditions.
Technical Specifications
The table below shows key parameters for system selection and operation.
| Parameter | Value |
|---|---|
| Power Supply | 95–240Vac, 50/60Hz |
| Power Consumption | WiFi 3W Max |
| Temperature Range | 5–95°C (41–203°F) |
| Floor Limit | 20–90°C (68–194°F) |
| Control Deviation | 0.5–10°C (Factory +1°C) |
| Ambient Temperature | -5–50°C |
| Protection Level | IP20 |
| Warranty | 2 Years |
Wiring Diagram
The diagram shows typical wiring for a four-pipe fan coil system. It includes fan control and separate heating and cooling valves.
Model Code Guide
The table below helps explain model options and system configuration.
| Model | Application |
| 843 | Timer + 2-pipe system |
| 853 | Timer + 2-pipe + limit sensor + room card + WiFi |
| 863 | Timer + 4-pipe + limit sensor + room card + WiFi |
| S | RS485 Modbus |
| Example HTW-WF81-FC-xxx | If xxx=863S, it means 3 fan speed, 4-pipe system, Wifi + Modbus |
Project Fit & Customization
This model is not suitable for systems that need modulating valve control. It does not support advanced PID logic. It may also not fit projects requiring special communication protocols.
Despite these limits, some functions can be adjusted. Modbus settings and communication details can be customised. Sensor inputs and control logic can also be discussed.
OEM support is available for branding and design updates. Logo printing, colour changes, and labels can be customised. Packaging and interface layout can also be adjusted.
Certifications and Compliance
The thermostat meets common European standards and test requirements.
Exhibition Moments
Our team participates in international HVAC exhibitions and events.
Frequently Asked Questions
Q1: Can this thermostat work with four-pipe systems?
Yes, it supports standard four-pipe fan coil systems. It controls both heating and cooling valves. Please confirm wiring before installation.
Q2: Does it support BMS integration?
Yes, it uses RS485 Modbus communication. This allows connection to building systems. The Smart Rs485 Modbus Thermostat supports central monitoring.
Q3: Can it work without WiFi?
Yes, it can work without WiFi. Modbus can be used for control. WiFi is optional depending on the project.
Q4: Is it suitable for residential use?
Yes, it is designed for homes and light commercial spaces. It fits common indoor environments. Installation is simple.
Q5: What is the MOQ and can I get samples?
We support samples for testing. Standard MOQ is 300 units. Smaller quantities like 100 units can be discussed.
Q6: How to place an order and arrange shipping?
Contact us to confirm requirements and receive a PI. Payment supports TT, PayPal, and Visa. Shipping terms include EXW, FOB, and DAP.
Q7: How long does production take?
Non-custom samples ship within 7 days. Custom orders take about 3–5 weeks. Bulk orders around 300 units need about one month.
Q8: What shipping methods are available?
Express delivery takes about 7 days. Air freight is similar. Sea freight takes about one month depending on route.
Need Support?
If you are planning a project or selecting a model, feel free to contact us. We can help review your system and suggest suitable options.
Related Thermostat Models
This section lists related thermostat models for different system types and integration needs, helping you choose a suitable option for your project.
More product details, please click here directly:
In HVAC projects, stable control and simple operation are important. This Smart Rs485 Modbus Thermostat manages fan speed and valve output clearly. It supports reliable system operation and helps improve building management. Learned more Modbus Thermostat
