Quick Summary
The HTW-WF71-853S is designed for indoor fan coil unit systems in homes and light commercial spaces. It controls a three-speed fan and one heating or cooling valve in a two-pipe system. The unit uses simple on/off logic to manage room temperature. WiFi and Modbus allow both remote control and system integration.
This WiFi Room Thermostat is used in projects that need stable control and simple BMS connection. 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 flexible use in fan coil systems.
(01) WiFi application control
WiFi allows users to adjust settings through a mobile app. This reduces manual work on site. The WiFi Room Thermostat improves daily control efficiency.
(02) 3-speed fan and valve control
The thermostat supports low, medium, and high fan speeds. It also controls one heating or cooling valve in a two-pipe system. This setup matches common FCU layouts.
(03) Programmable scheduling
Weekly programming allows automatic temperature changes during the day. This helps reduce energy use when rooms are empty. It also keeps indoor comfort stable.
(04) Function knob and multi-language support
The knob allows quick setting changes with simple rotation and press. Multi-language support makes operation easy in different regions. It improves user experience.
(05) Modbus communication
Modbus allows connection to BMS systems. It supports central monitoring and control. This WiFi Room Thermostat fits building management projects.
Product Design and Display
The design is simple and modern for indoor use. The knob control makes operation easy. The display 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 fan coil systems. It includes fan speed outputs and valve control connections. It also shows Modbus communication wiring for system integration.
Model Code Guide
(This section explains what each part of the model code means for system configuration.)
| Model | Application |
| 843 | Timer task + 2-pipe system+ Wifi |
| 853S | Timer task + 2-pipe system + Potential-free output- limit sensor (optional) + Room card (optional) +Wifi+Modbus |
| 863 | Timner task + 4 pipe system + Potential-free output- limit sensor (optional) + Room card (optional） +Wifi |
| 963 | Floor heating & fan coil, weekly programming+ Potential-free output + Timer task+ limit sensor (optional)+ Room card (optional) +Wifi |
| S | 485Modbus |
| Example HTW-WF71-FC-xxx | If xxx=853S, it means 3 fan speed+1 H/C valve, 2-pipe, Wifi, Modbus |
Project Fit & Customization
This model is not suitable for systems that require modulating control. It does not support 0–10V output or advanced PID logic. It may also not fit projects that need multi-stage control.
Despite these limits, some functions can be adjusted. Communication settings and control logic can be modified. Interface layout and system options 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 related test requirements.
Exhibition Moments
Our team participates in international HVAC exhibitions and industry events.
Frequently Asked Questions
Q1: Can this thermostat be used for fan coil systems?
Yes, it is designed for fan coil units. It controls fan speeds and valves. Please confirm wiring before installation.
Q2: Does it support BMS integration?
Yes, it supports Modbus communication. This allows connection to building systems. The WiFi Room Thermostat supports central monitoring.
Q3: Can it be controlled remotely?
Yes, WiFi allows app control. Users can adjust settings remotely. It is suitable for daily use.
Q4: Is it suitable for residential use?
Yes, it fits homes and small commercial spaces. Installation is simple. Daily use is easy.
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, please 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.
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In HVAC projects, stable control and system integration are important. This WiFi Room Thermostat combines fan coil control with Modbus communication. It helps improve system efficiency and supports comfortable indoor environments.
