Thermokon JOY HC AO2DO | HC 3AO | RS485 Modbus

Datasheet

Technical changes reserved. Valid as of: 13.06.2025

Production date on the product label on the device. Please observe.

Application

JOY HC AO2DO (85..260 V~)

The room thermostat has two switching outputs for heating/cooling with 230 V and an analog 0..10 V output for a 6-way valve for individual temperature control in residential and commercial spaces. The modern design combines a 2.5" LCD display with a touch interface. The device is designed for installation in a flush-mounted box.

JOY HC 3AO (24 V ~/=)

The room thermostat has 2 analog outputs (0..10V) for heating and cooling valves, as well as an analog output (0..10V) for a 6-way valve. The modern design combines a 2.5" LCD display with a touch interface. The device is designed for installation in a flush-mounted box.

Safety Instructions - ATTENTION

Installation and assembly of electrical devices (modules) may only be carried out by an authorized electrician.

The device is intended for use only as specified. Unauthorized modification or alteration is prohibited! The modules must not be used in conjunction with devices that directly or indirectly serve human, health, or life-saving purposes, or whose operation could endanger people, animals, or property. Connecting devices with a power connection must only be done after the connection line has been de-energized!

CAUTION! Risk of electric shock! Live parts may be present inside the housing. Particularly with devices operating at mains voltage (typically between 90 and 265 V), contact with live parts can result in personal injury.

Furthermore, the following apply:

• Laws, standards, and regulations
• The state of the art at the time of installation
• The technical data and the operating manual of the device

Product Testing and Certification

Declarations of conformity for the products can be found on our website: https://www.thermokon.de/direct/categories/joy-hc

Disposal Notice

The symbol of the crossed-out garbage can indicates that the product or removable batteries must not be disposed of with household or commercial waste. Within the EU, you are legally obliged to dispose of the product separately and appropriately according to the national laws of your country. Alternatively, contact your supplier or Thermokon Sensortechnik GmbH. Further information can be found at: www.thermokon.de

Installation Instructions for Room Sensors

The accuracy of room sensors is influenced by positioning and installation method, in addition to technical specifications.

To be observed during installation:

• Seal flush-mounted boxes (if available).
• Mounting location, drafts, heat sources, radiant heat, or direct sunlight can affect measurement acquisition.
• Building material-specific properties of the mounting location (brick, concrete, plaster, hollow walls, ...) can affect measurement acquisition.

Installation is not recommended in...

• Drafts (e.g., in the immediate vicinity of windows / doors / vents ...),
• Immediate vicinity of heat sources,
• Direct sunlight
• Niches / between furniture / ...

Installation Instructions

Hollow wall boxes should be covered by the wall covering after installation, otherwise the support rim of the hollow wall box lying on the wall will be visible from the side. If necessary, use white hollow wall boxes (i.e., Kaiser 9063-77).

User Information

Software

Software description at https://www.thermokon.de/

MicroSD Card

Storage medium for updates, upgrades, or configuration. Formatting in FAT file system required. NTFS and exFAT file systems are not supported!

Bootloader

A MicroSD card bootloader for applications (update, upgrade) or configurations is integrated into the device. Active bootloader = Ring illumination flashes (1 sec. interval), display is not controlled.

Firmware Update

• Remove the top cover, insert MicroSD card with valid update file, place top cover on bottom cover.
• Valid update file is recognized and update process is started (ring illumination flashes at 300ms interval).
• New application starts after update (approx. 20-30 sec.).
• Remove top cover to remove MicroSD card from device!

Device Configuration

• Remove top cover, insert MicroSD card with device configuration file, place top cover on bottom cover.
• Configuration file is recognized and device is configured.
• Device is ready for operation.
• Remove top cover, remove MicroSD card from device, place top cover on bottom cover.

Parameters for display, setpoints, and controller can only be changed via the configuration software.

Notes on Update Function

A device software update is only possible within the main version numbers.

Example:

• 3.0.2 ➔ 3.0.11
• 2.6.6 ➔ 2.3.0
• 2.x ➔ 3.x
• 2.x ➔ 4.x

Configuration via uConfig | MicroSD Card or Modbus

Configuration Software:

uConfig | Windows 10 required for using the uConfig configuration software.

The JOY room thermostat can be parameterized using the uConfig configuration software. The created configuration file is transferred to the device via an SD card. With Modbus devices, live configuration can also be carried out via the BUS interface.

The installer for the configuration software can be found in the download area on our website. The installer retrieves all necessary files and plug-ins from our web server. This version includes an update function in the software.

Download Area

Technical Data

JOY HC AO2DO | HC 3AO

*Humidity and CO2 measured values are not processed internally. The values are displayed and can be read by higher-level systems for evaluation and further use.

JOY HC AO2DO

JOY HC 3AO

*Supply Voltage: When supplying multiple bus devices from a 24V AC voltage source, ensure that all "positive" operating voltage inputs (+) of the field devices are connected together, as well as all "negative" operating voltage inputs (-) = reference potential (phase-synchronous connection of the field devices).

If the supply voltage is reversed on one of the field devices, a short circuit of the supply voltage will be generated through this device. The resulting short-circuit current flowing through this field device will damage the device. Therefore, pay attention to correct wiring.

Function Description – Controller

JOY HC AO2DO (85..260 V~)

PI controller (PWM) & Two-point/Three-point controller (configurable)

6WV (PI controller 0..10V) (all types)

The resulting control variable is output as a proportional control signal to the 6-way valve. The type of valve used is set via the configuration software. The following are available: 2..10 V / 2..10 V INV (Belimo), 0..10 V DN15/DN15 INV, DN20/DN20 INV (Sauter). Additionally, a freely parameterizable 6-way valve (generic 6WV) is available.

Heating/Cooling with 2-point/3-point controller (only HC AO2DO)

In temperature control, the two-point controller only knows the switching states Heating ON and Heating OFF. The three-point controller also knows the switching state Cooling. As with the two-point controller, the three-point controller also works with switching hysteresis.

[Diagram showing heating and cooling control curves with hysteresis]

Heating/Cooling with PI controller (PWM) (only HC AO2DO)

The temporal behavior of the PI controller is determined by the parameters Xp and Tn. Due to the proportional component, the control variable reacts immediately to any control deviation, while the integral component only takes effect over time. The resulting control variable is output directly to the outputs as a pulse-width modulated signal.

Heating/Cooling with PI controller (0..10 V) (only HC 3AO)

The temporal behavior of the PI controller is determined by the parameters Xp and Tn. Due to the proportional component, the control variable reacts immediately to any control deviation, while the integral component only takes effect over time. The resulting control variable is output directly to the outputs as an analog 0..10 V signal.

CO2 + Humidity Measured Value

The CO2 sensor has a measuring range of 0..2000 ppm (1 ppm resolution). The sensor can be adjusted (for calibration with an external measuring device) or automatically self-calibrated.

The humidity sensor has a measuring range of 0..100% (0.1% resolution). The sensor can be adjusted (for calibration with an external measuring device).

The humidity and CO2 values can be read via bus or displayed on the screen. No internal processing of the value occurs!

Display

Value Screen

• Internal Sensor Values
• External Sensor Values (configurable) (Humidity / CO2 value additionally configurable depending on the device)

Header (Value/Symbol Display)

• Time, Day of the week, Date, ECO symbol (depending on mode)
• Alarm symbol (overrides ECO symbol)

Footer (Symbol Display)

• Symbols for states: Heating, Cooling, Room occupancy, Window contact, etc.

The "Active Time Channel" symbol is only displayed if a channel is active.

[Screenshots of the device display showing different information: current temperature, date, CO2 and humidity values]

Function Description – Buttons

The touch surface has adjustment options for setting the setpoint.

Each button press illuminates the Power button ring as button feedback.

Setpoint adjustment (stepwise ± 3 °C, Power button for standby mode, default setting, configurable).

[Diagram showing button functions: up/down for setpoint, power button for standby/presence]

If no button is pressed for 3 seconds, the display returns to the main screen!

Standby Mode (not compatible with Keycard switch function)

In standby mode, the display and all outputs are switched off (controller deactivated). Frost and heat protection monitoring remain active.

[Diagram showing navigation menu: Up, Down, Left, Right for parameter menu; Right for opening submenu; Left for exiting submenu; Center for confirmation]

Diagnosis Menu

To access the diagnosis menu, select the header in the start window of the parameter menu and press the ENTER button. Here you can find various information, such as device type, software version, status of inputs and outputs, and controller status (current control variable).

Parameter Menu – Modbus Interface

The menu for setting the Modbus parameters is accessed by simultaneously pressing the marked buttons "Up" (A) and "Down" (C) for at least 5 seconds.

The menu is unlocked for the first 60 minutes after switching on the supply voltage, as long as the device is not actively integrated into Modbus communication. As soon as the device receives a valid request addressed to the device from a DDC, access to the menu is blocked. Without valid communication, access is blocked after 60 minutes!

Modbus Settings

Configuration

Parameter Menu

Access to Parameter Menu: Press Up and Down buttons simultaneously for 3 seconds.

[Diagram showing parameter menu navigation]

If no input is made for 8 minutes, the parameter menu will automatically exit!

Menu → Time Channels

Up to 3 time channels, each with 4 time segments, can be parameterized. The time channels are prioritized, with channel 3 having the highest priority.

Time Channel (4 Time Segments)

Weekday-Time Slot Configuration / + with Left/Right buttons

Time Segment

• Start - Setting start time (24h format)
• Fan - Selection of fan speed (type-dependent)
• Temperature - Setpoint (in °C or °F depending on configuration)
• ECO Mode - In ECO mode, the dead zone between heating and cooling is automatically set to the ECO dead zone configured in the "General Settings" menu (default: 10 K).

Menu → Time/Date

Under the Time/Date menu item, time, date, and display format can be configured.

An internal real-time clock automatically calculates time and date after initial configuration.

Menu → Sensor Settings

Display temperature value internal/external temperature sensors

Offset Int.: For temperature compensation of internal temperature sensor self-heating, an offset can be configured.

Offset Ext.: For temperature compensation of an connected external NTC10K, an offset can be configured.

Offset rH: For compensation of constant measurement deviations, a humidity offset can be configured.

Calib. CO2: Here, a measured value can be entered which is determined in the vicinity of the device using a reference measuring device (Calibration CO2 Sensor (Forced)).

ASC CO2: Switches the ASC (Automatic Self Calibration) function ON/OFF (factory setting ON).

Calibration CO2 Sensor (FORCED)

The combination of buttons (Top Left + Top Right) calibrates the currently detected air mixture in the device with the value configured in the display. This button combination only works in the CO2 sensor settings menu. The sensor must have been in operation for at least 3 minutes before calibration. Caution: CO2 sources (e.g., exhaled air) influence the measurement acquisition!

With a forced calibration, the ASC function is deactivated.

[Diagram showing button combination for forced CO2 calibration]

ASC (AUTOMATIC SELF-CALIBRATION)

The ASC function sets the lowest detected CO2 value (7-day period) as the reference value for measurement acquisition. Sufficient fresh air supply within the 7-day period is required to ensure accurate measurement results.

CO2 Factory Setting

To reset the sensor to factory settings, use the button combination. This button combination only works in the CO2 sensor settings menu.

[Diagram showing button combination for CO2 factory reset]

Menu → General Settings

General Device Settings:

• Brightness: Configuration of the brightness values for the LCD backlight / LED ring when buttons are pressed.
• Contrast: Configuration of the display contrast values.
• Ventilation Protection: A ventilation protection function regularly actuates valves to prevent them from seizing, even with prolonged non-use. The ventilation protection process takes place on Fridays at 5:00 AM for the heating valve and at 5:20 AM for the cooling valve. If the respective valve has not been actuated in the last 96 hours, it will be switched on for 5 minutes.
• ECO Dead Zone: Configures a hysteresis function. Default value 10.0K * *Further information in the software description.
• Fan Stages: Configuration of the device's fan stages.
• Language: Selection of the display language.
• Factory Reset: By selecting factory reset, the room thermostat restarts and is reset to the delivery state.

Inputs

Up to 2 inputs with different functions, such as window contact, dew point, room occupancy, change-over, external sensor, etc., can be configured. An overview of possible combinations can be found in the JOY software specification.

Connection Plan

JOY HC AO2DO (85..260 V~)

[Wiring diagram for JOY HC AO2DO]

JOY HC 3AO (24 V ~/=)

[Wiring diagram for JOY HC 3AO]

Note: Inputs for potential-free contacts must not be connected in parallel. If the operating mode (Change-Over DI) of multiple devices is to be switched by a single contact, the input for potential-driven contacts must be used. Care must be taken to ensure that the same phase is used for devices switched together.

Dimensions (MM)

[Diagram showing the dimensions of the room controller]

Optional Accessories

• Surface-mount frame Joy pure white - Art. No.: 760201
• Surface-mount frame Joy black - Art. No.: 760195
• Decorative frame pure white for JOY - Art. No.: 681452
• Decorative frame black for JOY - Art. No.: 740951
• MicroSD card 2GB - Art. No.: 500098
• RS485 Biasing Adapter - Art. No.: 811378
• USB RS485 Modbus RTU Logger - Art. No.: 809917
• USB Interface RS485 (incl. driver CD) - Art. No.: 668293