Versatile D Series Heating Thermostat

Versatile D series Heating Thermostat is a big family which is suitable for most kinds of heating and air-conditioning systems' terminal control or equipment control. For heating application, it is suitable for hydronic ﬂoor heating, electrical heating and FCU+ hydronic ﬂoor heating. Some models also provide local schedule and remote control via free mobile app which makes it easy to improve comfort and save energy. And models with RS-485 interface can be integrated by BA System via Modbus-RTU protocol.

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Description Technical Data Model List Wiring Diagram Installation Diagram

Description

The Versatile D Series Heating Thermostat is a comprehensive family of heating thermostats engineered for the terminal control of most hydronic floor heating, electrical heating, and FCU (Fan Coil Unit) + hydronic floor heating systems. As a reliable programmable thermostat, it is designed to deliver stable indoor comfort while reducing energy waste across residential, commercial, and industrial HVAC applications.

Selected models add a local programmable schedule and remote control via a free mobile app (WiFi), making it easy to improve comfort and save energy from anywhere. Models equipped with an RS-485 interface can be integrated into a Building Automation (BA) System through the Modbus-RTU protocol, enabling centralized monitoring and energy management. Whether you need a smart thermostat for hydronic heating, an electrical heating thermostat, or an FCU thermostat, the Versatile D Series offers a matched model for your project.

Explore the full Hailin heating thermostat range or compare with the Vivid Series and HA209 Series for alternative form factors.

Key Features

Press Button & Button Lock

Tactile press-button operation with a button lock function prevents unauthorized or accidental changes — ideal for public and rental spaces.

White Backlight Display

A clear white backlight LCD ensures easy reading of room and set temperatures in low-light conditions.

Power Restoration (Up Power)

Up power restoration automatically recovers your previous settings after a power outage, avoiding comfort interruptions.

On/Off Timer

A built-in On/Off timer lets you schedule automatic start and stop times to match occupancy and cut standby energy use.

Programmable Schedule (5-2, 4 Periods)

Models with a programmable schedule support a 5-2 day, 4-period weekly plan for personalized comfort and energy savings.

Anti-Freezing Protection

Anti-freezing protection keeps pipes and the space safe in cold seasons by maintaining a minimum temperature.

Over-Heating Protection

Selected electrical heating models include over-heating protection for safe high-current operation (see model list).

Remote & Smart Control

WiFi models offer remote control via a free mobile app, while RS-485 models enable Modbus-RTU integration into BA systems.

Technical Data

Room Temp Accuracy :+1°C

Display Temp Resolution : 0.5°C

Environmental:
Operating Temperature Range: 0-45°C ;

Operating Humidity Range: 5-95% RH
Power Consumption: <2 W
Power supply: AC85-250V, 50 /60Hz
Terminations:
Hydronic Heating Model: one 2.5mm2 or two 1.5mm2 wiresElectrical

Heating Model: one 4mm2
Max Load Current:
Hydronic Heating Model: <2A (resistive), <1A (inductive)

Electrical Heating Model: <16A (resistive), <6A (inductive)

Dim. H x W x D(mm):86x86x15.5
Mounting Hole Dim.: 60mm
Protection Class: IP30
Compatible Remote Sensor Type: NTC10k B=3950

Model List

Model

Connectivity

Type of FCU

Type of Actuator

Type of Fan

OnOff Timer

Schedule

Remote Sensor

DO
(Dry Contact)

Note

RS-485

Wi-Fi

2-Pipe

4-Pipe

2-Wire

3-Wire

AC 3-Speed Motor Fan

5-2
(4 Periods)

HA223-L

√

Hydronic

HA8223-TL-MD

√

HA9223L-L

√

HA8323-S2TL-MD

√

Over-heating Protection

Electrical

HA9323-S2L

√

Over-heating Protection

HLA2023DA2-L

√

Hydronic FCU

HLA2023DB2-L

√

HLA2023DAL-L

√

HLA2023DBL-L

√

HLA9023DB-L

√

HLA9023DA2-L

√

HLA9023DB2-L

√

HLA9023DAL-L

√

HLA9023DBL-L

√

Applications

Thanks to its broad model range, the Versatile D Series Heating Thermostat fits a wide spectrum of HVAC control scenarios:

Residential communities & villas — smart heating for apartments and homes with WiFi scheduling and energy savings.

Hotels & hospitality — hotel building automation using FCU + hydronic floor heating control per room.

Commercial office complexes — centralized comfort and energy management via RS-485 Modbus-RTU.

Hospitals & healthcare — stable, reliable temperature control for patient areas.

Laboratories — precise environmental control for sensitive spaces.

Data centers & telecom — temperature monitoring integrated into BA systems.

Transportation & public facilities — heating control for stations and public buildings.

Industrial parks — building energy-management solutions with centralized control.

See proven deployments such as the EBA Building Automation at Zhongguancun Science City and the Qinhuangdao Bovi Fortune Center thermal-storage project.

Compatibility & Building Automation Integration

Models with an RS-485 interface expose the Modbus-RTU protocol, allowing the thermostat to be integrated into a Building Automation (BA) System through Hailin gateways and controllers. This enables:

Centralized scheduling and setpoint management across zones;
Real-time energy consumption monitoring and optimization;
Integration with Hailin sensors, gateways and professional HVAC services.

For wireless projects, WiFi models connect to a free mobile app for remote control without additional building wiring.

Why Choose Hailin Controls

Hailin Controls is an experienced HVAC control manufacturer with internationally recognized certifications and a full portfolio of thermostats, sensors, gateways and building-management platforms. The Versatile D Series reflects Hailin's commitment to reliable, energy-efficient and easy-to-deploy control solutions for global projects.

Frequently Asked Questions

What heating systems are compatible with the Versatile D Series Heating Thermostat?

It supports hydronic floor heating, electrical heating, and FCU + hydronic floor heating systems. Choose the model that matches your actuator type (2-wire/3-wire), FCU configuration (2-pipe/4-pipe) and load requirement.

Does the thermostat support WiFi and mobile app control?

Yes. WiFi-enabled models provide remote control via a free mobile app, letting you set schedules, adjust temperature and monitor energy use from anywhere.

What is the temperature accuracy and display resolution?

Room temperature accuracy is ±1°C with a display resolution of 0.5°C, using a compatible NTC10k (B=3950) remote sensor.

What are the mounting dimensions?

Dimensions are 86 × 86 × 15.5 mm (H×W×D) with a 60 mm mounting hole and IP30 protection class — a standard flush-mount 86-box format.

Wiring Diagram

Installation Instructions

APPLICATION

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Versatile D Series Heating Thermostat

Description

Key Features

Press Button & Button Lock

White Backlight Display

Power Restoration (Up Power)

On/Off Timer

Programmable Schedule (5-2, 4 Periods)

Anti-Freezing Protection

Over-Heating Protection

Remote & Smart Control

Technical Data

Model List

Applications

Compatibility & Building Automation Integration

Why Choose Hailin Controls

Frequently Asked Questions

What heating systems are compatible with the Versatile D Series Heating Thermostat?

Does the thermostat support WiFi and mobile app control?

What is the temperature accuracy and display resolution?

What are the mounting dimensions?

Wiring Diagram

Installation Instructions

APPLICATION

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