Thermokon JOY Fancoil Modbus RS485 Data Sheet
Fancoil-Regler (ab Version 4.x)
Data Sheet
Technical changes reserved. Valid as of: 13.06.2025 A145
Valid from production date: See product label on the device.
JOY Fancoil 5DO RS485 Modbus (85..260 V ~)
Fancoil thermostat for controlling a 3-speed fan. Designed for fan coil units with 2- and 4-pipe systems. Features a modern design with a 2.5" LCD display and a touch surface. Allows setting of 3 time channels, each with 4 time segments. Designed for installation in a flush-mounted box.
JOY Fancoil EC AO2DO RS485 Modbus (85..260 V ~)
Fancoil thermostat for controlling fan coil units with EC fans. Suitable for 2- and 4-pipe systems. Includes 2 relays and 1 analog output 0-10V (heating valve, cooling valve, and EC fan). Features a modern design with a 2.5" LCD display and a touch surface. Allows setting of 3 time channels, each with 4 time segments. Designed for installation in a flush-mounted box.
JOY Fancoil EC 3AO RS485 Modbus (24 V ~/=)
Fancoil thermostat for controlling fan coil units with EC fans. Suitable for 2- and 4-pipe systems. Includes 3 analog outputs 0-10V (EC fan, heating valve, and cooling valve). The heating and cooling valve outputs can also be used for 6-way valves. Features a modern design with a 2.5" LCD display and a touch surface. Allows setting of 3 time channels, each with 4 time segments. Designed for installation in a flush-mounted box.
Safety Notice – ATTENTION
Warning! Installation and assembly of electrical devices (modules) must only be carried out by an authorized electrician.
The device is intended for its designated use only. 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 that could pose a danger to people, animals, or property through their operation. Connection of devices with a power supply must only be carried out when the connection line is de-energized!
CAUTION! Risk of electric shock! Voltage-carrying parts may be present inside the housing. Especially with devices operating at mains voltage (normally between 90 and 265 V), touching voltage-carrying 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
Declaration of Conformity
Explanations regarding product conformity can be found on our website: https://www.thermokon.de/direct/categories/joy-fancoil
DISPOSAL NOTICE
The symbol of the crossed-out waste bin 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 GUIDELINES – 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).
- Installation location, drafts, heat sources, radiant heat, or direct sunlight can affect measurement acquisition.
- Building material-specific properties of the installation location (brick, concrete, cavity walls, etc.) can affect measurement acquisition.
Installation is not recommended in...
- Drafts (e.g., close proximity to windows/doors/vents...),
- Close proximity to heat sources,
- Direct sunlight
- Niches / between furniture / ...
INSTALLATION GUIDELINES
Cavity wall boxes should be covered by the wall covering after installation, as the support rim of the cavity wall box lying on the wall would otherwise be visible at the side under the device. If necessary, use white cavity 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 the MicroSD card with a valid update file, place the top cover back onto the base. The valid update file is recognized and the update process starts (ring illumination flashes at 300ms interval). New application starts after update (approx. 20-30 sec.). Remove the top cover to remove the MicroSD card from the device!
Device Configuration
Remove the top cover, insert the MicroSD card with the device configuration file, place the top cover back onto the base. The configuration file is recognized and the device is configured. Device is ready for operation. Remove the top cover, remove the MicroSD card from the device, place the top cover back onto the base.
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 same major version number.
Version Compatibility:
- 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 | Requires Windows 10 for the use of 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. For Modbus devices, live configuration can also be performed 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 integrated software update function. Download area: https://www.thermokon.de/download
TECHNICAL DATA
JOY Fancoil 5DO | JOY Fancoil EC AO2DO | JOY Fancoil EC 3AO
| Measured Variables | Temperature, Humidity* (optional), CO2* (optional) | |
| Network Technology | RS485 Modbus RTU, Fail-safe Biasing required | |
| Temperature Measuring Range | 0..+50 °C | |
| Temperature Accuracy | ±1 K (typical at 21 °C) | |
| Humidity Measuring Range (optional) | 0..100% RH without condensation | |
| Humidity Accuracy (optional) | ±2% between 10..90% RH (typical at 21 °C) | |
| CO2 Measuring Range (optional) | 0..2,000 ppm | |
| CO2 Accuracy (optional) | (5% of measured value) + 50 ppm | |
| Control Functions | Setpoint adjustment 0..+50 °C, Fan stages | |
| Display | LCD 2.5", 240x160 px., White backlight | |
| Functions | Integrated PI and two-point/three-point controller, 2nd control loop: Two-point controller | |
| Housing | PC and glass, optionally black or white | |
| Protection Class | IP30 according to DIN EN 60529 | |
| Electrical Connection | Terminals 1..8: Screw terminals max. 1.5 mm² | Terminals 9..12: Screw terminals max. 1.0 mm² |
| Ambient Conditions | 0..+50 °C, max. 85% RH non-condensing | |
| Weight | 195 g | |
| Mounting | Flush-mounted in standard flush-mounted box (Ø=60 mm) |
*Humidity and CO2 measured values are not processed internally. The values are displayed and can be read out by higher-level systems for evaluation and further use.
JOY Fancoil 5DO
| Output Switching Contact | 3x Normally Open contacts (Fan stages), 240 V, max. load 3 A | 2x Normally Open contacts (Heating & Cooling), 240 V, max. load 500 mA |
| Voltage Supply | 85..260 V ~ | |
| Power Consumption | max. 2.5 VA (260 V ~) | |
| Inputs | DI1: Input for NTC10k or potential-free contact | DI2: Digital input, for potential-driven contact (230 V ~) |
JOY Fancoil EC AO2DO
| Output Voltage | 1x 0..10 V, max. load 5 mA, control EC fan | |
| Output Switching Contact | 2x Normally Open contacts (Heating & Cooling) 240 V, max. load 500 mA | |
| Voltage Supply | 85..260 V ~ | |
| Power Consumption | max. 3 VA (260 V ~) | |
| Inputs | DI1: Input for NTC10k or potential-free contact | DI2: Digital input, for potential-driven contact (230 V ~) |
JOY Fancoil EC 3AO
| Output Voltage | 3x 0..10 V, max. load 5 mA, control EC fan, heating & cooling or control of 6-way valve (configurable via software) | |
| Voltage Supply | 24 V = (±10%) or 24 V ~ (±10%) SELV | |
| Power Consumption | max. 2.5 W (24 V =) | |
| Inputs | DI 1: Input for NTC10k or potential-free contact | DI 2: Digital input, for potential-driven contact |
*Voltage Supply: If multiple bus devices are supplied by a 24V AC voltage, 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 this device. Therefore, pay attention to correct wiring.
FUNCTIONAL DESCRIPTION – CONTROLLER/FAN STAGES
JOY Fancoil 5DO (85..260 V~)
PI Controller (PWM) & Two-point/Three-point controller (configurable)
JOY Fancoil EC AO2DO (85..260 V ~)
PI Controller (PWM) & Two-point/Three-point controller (configurable)
JOY Fancoil EC 3AO (24 V ~/=)
PI Controller (0..10 V)
The fan stages are coupled to the controller in automatic mode. The assignment of the fan stage to the control (heating/cooling, heating only, cooling only) is freely selectable. To ensure safe fan startup, a time can be parameterized during which the fan runs at maximum speed. If one or more time channels are used, the fan control function is set for each time channel and each segment when configuring the time channels. The user can override the setting at any time by operating the device. At the beginning of the next time channel segment, the speed is set to the configured value. When a presence change (occupied ➔ unoccupied) occurs, the fan is set to automatic mode.
Heating/Cooling with PI Controller (PWM) (only 5DO and EC AO2DO)
The temporal behavior of the PI controller is set 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 2-point/3-point controller (only 5DO and EC 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. Like the two-point controller, the three-point controller also works with a switching hysteresis.
Heating/Cooling with PI Controller (0..10 V) (only EC 3AO)
The temporal behavior of the PI controller is set 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.
EC Fan in Automatic Mode with PI Controller (only EC 3AO and EC AO2DO)
(For EC AO2DO with two-point/three-point controller, the temperature range for controlling the 0..10 V EC fan is parameterized separately)
The fan speed 0..10 V (0..100%) is controlled proportionally to the calculated control variable of the PI controller.
Example: Calculated control variable: 65% = Fan control: 6.5 V
EC Fan in Manual Mode with PI Controller (only EC 3AO and EC AO2DO)
Calculated control variable: 22% = Fan control: 2.2 V
The number of steps is linearly distributed to the control variable from 0..100% (up to 5 steps adjustable via configuration software).
Example: Max. Steps = 5
Step 1 = 20% | Step 2 = 40% | Step 3 = 60% | Step 4 = 80% | Step 5 = 100%
CO2 + Humidity Measured Value
Max. Steps = 3
Step 1 = 33% | Step 2 = 66% | Step 3 = 100%
The CO2 sensor has a measuring range of 0-2000 ppm (resolution 1 ppm). 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% (resolution 0.1%). The sensor can be adjusted (for calibration with an external measuring device).
Humidity and CO2 values can be read out via bus or displayed. No internal processing of the values occurs!
SCREEN DISPLAY
Internal Sensor Values
23.3 °C
AUTO 1
External Sensor Values (configurable)
(Humidity/CO2 values can be additionally configured depending on the device)
686 ppm
56.6 %rH
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 symbol "Active Time Channel" is only displayed if a channel is active.
Heating/Cooling
Fan Stage
Active Time Channel
FUNCTIONAL DESCRIPTION – BUTTONS
The touch surface allows for setpoint and fan stage adjustments. The ring of the Power button illuminates with each button press for feedback.
Fan Stage Adjustment: "Fan Stage Up" / "Fan Stage Down"
Setpoint Adjustment: "± 3 °C, standard setting, configurable"
Power Button: For standby mode or presence sensor function*
*If the Power button is used as a presence button simultaneously, the button must be pressed for at least 3 seconds. In all other cases, a short press is sufficient.
If no button is pressed for 3 seconds, the display returns to the main screen!
Standby Mode (cannot be combined with Keycard Switch function)
In standby mode, the display and all outputs are switched off (controller deactivated). Frost and heat protection monitoring remains active. Modbus registers can still be read (e.g., room temperature).
Navigation Parameter Menu (Up, Down, Left, Right)
Open Submenu (Right)
Exit Submenu (Left in header)
Confirmation
DIAGNOSTIC MENU
To access the diagnostic menu, mark the header in the parameter menu start window 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
To access the menu for setting Modbus parameters, press and hold the "Up" (A) and "Down" (C) buttons simultaneously for at least 5 seconds.
The menu is unlocked for the first 60 minutes after power-on, as long as the device is not actively integrated into Modbus communication. As soon as the device receives a valid request addressed to it from a DDC, access to the menu is blocked. Without valid communication, access is blocked after 60 minutes!
Modbus Settings
- Address: 32 (Standard: 32) Address in the Modbus network. Addresses 1-247 can be set.
- Baud Rate: 19200 (Standard: 19200) 9600Bd | 19200Bd | 38400Bd | 57600Bd
- Parity: Even (Standard: Even) None | Odd | Even
CONFIGURATION
Parameter Menu
Access to Parameter Menu: Press and hold the buttons for 3 seconds simultaneously.
Menu Options:
- Time Channels
- Time/Date
- Sensor Settings
- General Settings
The parameter menu is automatically exited if no input is made for 8 minutes!
MENU → TIME CHANNELS
3 time channels, each with 4 time segments, can be parameterized. The time channels are prioritized, with Channel 3 having the highest priority.
| Time Channels | Time Channels / Timer1 | Segments / Segment 1 | Time | Fan | Temp | Abs. End. |
| Time Channel 1 | Mon - Fri | Start | 06:00h | AUTO | 22.0° | |
| Time Channel 2 | Mon | End | 08:30h | 1 | 20.0° | |
| Time Channel 3 | Fri | 16:00h | A | 22.0° | ||
| 22:30h | 0 | 22.0° | ECO |
Time Channel (4 Time Segments)
Weekday-Time Period Configuration / + with Left/Right Buttons
- Time Segment
Start - Setting start time (24h format)
Fan - Select fan stage (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, the time, date, and display format can be configured.
| Menu | Time Setting/Time | Time Setting/Date | Standard Settings: |
| Time Channels | Hour | Day | 12h/24h display |
| Time/Date | Minute | Month | 24h |
| Sensor Settings | Year | Time changeover (Summer/Winter time) according to CET | |
| General Settings | Time changeover <-/+> CET | Display <-/+> D.M.Y | Date display Day.Month.Year |
An internal real-time clock automatically calculates the time and date after initial configuration.
MENU → SENSOR SETTINGS
Display of temperature values from internal/external temperature sensors
| Menu | Internal Temperature Sensor Settings | External Temperature Sensor Settings | |
| Time Channels | Offset int. | Internal Value | External Value |
| Time/Date | Offset ext. | 22.1°C | 22.1°C |
| Sensor Settings | Offset rH | +0.0% | +46.8% |
| General Settings | Calib. CO2 | +560ppm | OFF |
| ASC CO2 | +643ppm |
Offset int.: An offset can be configured for temperature compensation of the internal temperature sensor's self-heating.
Offset ext.: An offset can be configured for temperature compensation of a connected external NTC10K.
Offset rH: An offset can be configured to compensate for constant measured value deviations.
Calib. CO2: Here, a measured value can be entered that was determined in the vicinity of the device using a reference measuring device (CO2 sensor calibration (Forced)).
ASC CO2: Switches the ASC (Automatic Self Calibration) function ON/OFF (Factory setting: ON).
CALIBRATION CO2 SENSOR (FORCED)
Using the button combination (Up Left + Up Right), the currently measured air mixture in the device is calibrated with the value configured in the display. This button combination only works in the CO2 sensor settings menu.
Attention: CO2 sources (e.g., breathing air) affect measurement acquisition!
With forced calibration, the ASC function is deactivated.
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.
MENU → GENERAL SETTINGS
| Menu | Settings/General | Settings/General | Settings/Language |
| Time Channels | LCD Brightness <-/+> | Ventilation Protection | Deutsch |
| Time/Date | LED Brightness <-/+> | ECO Dead Zone | English |
| Sensor Settings | Contrast <-/+> | Fan Stages | |
| General Settings | General | Language | Factory Reset |
General Device Settings:
- Brightness: Configuration of the LCD backlight brightness / LED ring brightness 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 runs every Friday 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 preceding 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: Selecting factory reset restarts the room thermostat and resets it 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.
- Sensor (NTC10K): If an external sensor is connected and the input is configured accordingly, its value is displayed. In this case, the thermostat regulates based on the value of the external sensor. Alternatively, an external temperature sensor can be used on the universal input to protect an underfloor heating system. If a configured temperature is exceeded, the heating sequence is suspended.
- Change-Over DI: The digital input is used to switch between heating and cooling modes. Depending on the state of the contact, only the heating controller or only the cooling controller is active in the room thermostat (default setting, contact open: heating controller active, contact closed: cooling controller active, input signal configurable via parameter "Polarity"). Terminals 4 and 5 are used in parallel as outputs for heating or cooling, respectively.
- Change-Over Sensor: The change-over sensor is used for automatic switching between heating and cooling modes. The limit temperatures for heating and cooling can be configured.
- Window Contact/Energy Save: If the digital input is configured as change-over, the room thermostat automatically operates in 2-pipe mode, and both outputs (terminals 4 and 5 [3AO: terminals 3 and 4]) are used in parallel as outputs for heating or cooling.
- Dew Point: If the universal input is configured as a changeover sensor, the measurement of the medium temperature can be controlled via various parameters. Up to two measurements can be performed per day, for which the opening time of the valves and the start and subsequent duration of the medium temperature measurement can be configured. During the active opening time and after a faulty medium measurement (invalid temperature), the controller mode display alternates between the heating and cooling symbols if activated. Further information in the software description.
- Presence: The room thermostat has an energy-saving function that is activated via the input with the window contact function. When the window contact/energy save is active, the setpoints for frost protection or heat protection are active.
- Keycard Switch: An active dew point contact blocks the cooling controller.
- Alarm Contact: When the presence function is activated, the presence symbol is automatically displayed. In the "Room unoccupied" state, the heating setpoint is reduced by 2K (default) or the cooling setpoint is increased accordingly.
- If the card is not inserted, the device switches to energy-saving mode. Button operation is locked, the display is switched off, and the controller regulates to the setpoints of the "room unoccupied" state.
- An alarm symbol can be displayed in the header of the display. When an alarm is active, the backlight flashes. This symbol is located in the same position as the ECO symbol. Since the alarm symbol has higher priority, it overrides the ECO symbol!
CONNECTION DIAGRAM
JOY Fancoil 5DO (85..260 V~)
1 Fan Stage 3
2 Fan Stage 2
3 Fan Stage 1
4 Cooling
5 Heating
6 Digital Input 2 (230V)
7 L
8 N
12 Modbus B
11 Modbus A
10 GND DI 1
9 Digital Input 1 (or NTC10K)
JOY Fancoil EC AO2DO (85..260 V ~)
1 EC Fan GND
2 EC Fan (0..10 V)
4 Cooling
5 Heating
6 Digital Input 2 (230V)
7 L
8 N
12 Modbus B
11 Modbus A
10 GND DI 1
9 Digital Input 1 (or NTC10K)
JOY Fancoil EC 3AO (24 V ~/=)
1 Digital Input 2
2 EC Fan (0..10 V)
3 Cooling (0..10 V) or 6-Way Valve
4 Heating (0..10 V) or 6-Way Valve
5 GND DI 2
6 GND
7 24 V = (±10%) or 24 V ~ (±10%)
8 GND
12 Modbus B
11 Modbus A
10 GND DI 1
9 Digital Input 1 (or NTC10K)
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 use the same phase when switching devices together.
DIMENSIONS (MM)
ACCESSORIES (OPTIONAL)
- Surface-mounted frame JOY pure white Art.-No.: 760201
- Surface-mounted 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
