SunTouch heated floor thermostats combine programmable precision with voltage flexibility, enabling fast floor heating control! The 500670‑SB auto‑schedules based on floor sensor data, while the 500675 offers 120/240 VAC compatibility. Follow the manual for setup, programming, and energy tracking.
Model Overview
SunTouch offers two primary thermostat models for heated floors. The 500670‑SB is fully programmable, automatically scheduling heating based on floor‑sensor input. The 500675 is non‑programmable, supporting dual 120/240 VAC operation for versatile installations. Enjoy heating.
Programmable 500670‑SB
The SunTouch 500670‑SB is a fully programmable floor‑heating thermostat that automatically determines the optimal start time to reach the setpoint temperature at the desired schedule. Its core feature is the auto‑scheduling function, which uses the floor sensor temperature to calculate when heating should begin, ensuring efficient energy use and consistent comfort. Users can disable this feature via the OPTIONS menu if manual control is preferred. The thermostat is factory‑set to operate based on the floor sensor, but can be re‑programmed to use ambient temperature if needed. The 500670‑SB supports dual voltage (120/240 VAC) and includes a built‑in energy monitoring display that records heating hours, allowing homeowners to track usage and estimate costs. The device offers a clear, backlit LCD for easy reading, with intuitive buttons for setting time, temperature, and schedule. The programmable schedule allows up to 7 days of custom settings, each with multiple time slots. The thermostat also features a “comfort mode” that can be activated to maintain a higher temperature during specific periods. The 500670‑SB’s design includes a robust housing that protects against moisture and dust, making it suitable for residential and commercial applications. Installation requires a floor sensor wire, which must be placed at least 1 inch into the heated area and secured to the wall stud or floor. The thermostat’s wiring diagram indicates a 20 A circuit for 120 VAC or 10 A for 240 VAC, with a neutral and ground connection. The unit’s firmware supports future updates, ensuring compatibility with evolving smart‑home ecosystems. Overall, the 500670‑SB delivers precise, programmable control, energy savings, and reliable performance for heated‑floor systems. Users can also link the thermostat to a mobile app for remote monitoring and scheduling, providing flexibility for on‑the‑go adjustments. The unit’s robust construction and user‑friendly interface make it an ideal choice for both new installations and retrofits, ensuring long‑term comfort and energy efficiency. All features are fully documented in the accompanying user guide!!!
Non-Programmable 500675
The SunTouch 500675 is a non‑programmable, dual‑voltage thermostat for floor‑heating systems. It supports 120 VAC and 240 VAC, allowing installers to match the heating load. The unit regulates the heating element by switching power on and off to maintain a single set temperature. Users set the desired temperature with the up/down buttons, and the thermostat keeps the floor at that setpoint until the target is reached. The display shows current temperature, setpoint, and mode. An energy‑monitoring feature records total heating hours, viewable on the LCD or via the serial port. Installation requires a floor sensor wire positioned at least 1 inch into the heated area and secured to the wall stud or floor. Wiring diagrams specify a 20 A circuit for 120 VAC or a 10 A circuit for 240 VAC, with neutral and ground. The thermostat’s housing protects against moisture and dust, suitable for indoor and outdoor use. It is factory‑set to use the floor sensor temperature but can be re‑configured for ambient temperature. A comfort mode can be activated to maintain a higher temperature during specific periods. The 500675 is compatible with SunTouch’s smart‑home ecosystem, enabling remote monitoring and control via the SunTouch ConnectPlus app. All features are documented in the user manual, which includes wiring diagrams, safety instructions, and troubleshooting tips. This thermostat offers reliable, low‑maintenance floor‑heating control while keeping energy usage transparent and manageable. The thermostat also features a quick‑start mode that allows immediate heating upon power restoration, ensuring consistent comfort during power outages. Its compact design fits easily into standard wall boxes, and the LED status indicator provides clear visual feedback on operation. Installation is straightforward, with clear labeling on the back panel to guide correct wiring. The thermostat’s firmware supports future updates, keeping the system current with evolving smart‑home standards. Users appreciate its quiet operation and reliability.
Key Features
SunTouch thermostats offer auto‑scheduling, floor‑sensor accuracy, dual‑voltage (120/240 VAC) support, and built‑in energy monitoring. The 500670‑SB auto‑starts heating to hit setpoint on time, while the 500675 delivers reliable, voltage‑flexible control. Ideal for residential and commercial use.!
Automatic Scheduling & Floor Sensor
The SunTouch 500670‑SB thermostat automatically determines the optimal start time for heating, ensuring the floor reaches the desired setpoint precisely when scheduled. This feature relies on a built‑in floor sensor that continuously monitors the actual floor temperature. By comparing sensor data with the user‑defined target, the unit calculates the required heating duration and initiates the cycle at the calculated moment. Users can enable or disable this auto‑schedule via the OPTIONS menu: press the OPTIONS button, hold for one second, then toggle the SSt setting to On or Off. When disabled, the thermostat operates in manual mode, allowing direct control of heating cycles.
The floor sensor is a thin, flexible cable that must be affixed to the floor surface, typically 1 inch below the heated area, and secured to a wall stud if necessary. Proper placement ensures accurate temperature readings and prevents false triggering. The sensor’s data is displayed on the thermostat’s LCD, showing real‑time floor temperature and the difference from the setpoint. This real‑time feedback allows users to adjust settings for optimal comfort and energy savings.
The auto‑schedule feature is especially useful for residential settings where occupants prefer a warm floor at a specific time, such as morning or evening. It also reduces energy consumption by avoiding unnecessary heating when the floor is already near the target temperature. The SunTouch manual provides step‑by‑step instructions for configuring the schedule, including setting start times, durations, and temperature limits. Users can also create multiple schedules for different days of the week, enabling flexible control for varying daily routines.
Additional benefits include the ability to monitor heating hours, which helps estimate energy usage and maintenance needs. The thermostat’s firmware supports firmware updates that can refine sensor calibration and scheduling algorithms, ensuring long‑term reliability. Safety features such as over‑temperature protection and fault detection are built into the sensor circuitry, alerting users to potential issues before they become serious.
If the sensor fails to read correctly, check for loose connections, ensure the cable is not kinked, and verify that the sensor is properly grounded. The manual includes a diagnostic routine that displays error codes on the LCD, guiding users to the root cause. In most cases, reseating the sensor or replacing the cable resolves the issue. For persistent problems, contact SunTouch support for advanced troubleshooting or replacement parts.
When paired with SunTouch ConnectPlus, the thermostat can transmit sensor data and schedule status to a mobile app, allowing remote monitoring and adjustments. This integration enhances convenience, especially for users who travel frequently or manage multiple heating zones. The app also provides alerts for temperature deviations and maintenance reminders, further extending the system’s functionality.
Calibration is performed automatically during the initial setup. The thermostat measures the ambient temperature and adjusts the sensor offset to match the floor’s thermal response. Users can manually fine‑tune the offset via the OPTIONS menu if they notice consistent temperature discrepancies.
Regular firmware updates ensure the scheduling logic remains optimal over time.
Dual Voltage Support
SunTouch 500675 is engineered to manage both 120 VAC and 240 VAC resistive floor systems. The thermostat’s internal transformer automatically detects the incoming voltage and routes the control signal to the heating circuit. Users select the voltage mode via the OPTIONS menu: press OPTIONS, hold for one second, then toggle between 120 VAC and 240 VAC. The display will show the current mode and a warning if the selected voltage does not match the connected supply.
Installation requires a dedicated 20 A circuit for 240 VAC or a 15 A circuit for 120 VAC, with a properly sized conduit and GFCI protection. The thermostat’s wiring diagram specifies a 14/3 or 12/3 cable, depending on voltage, with the neutral and ground connected to the panel. The device’s internal fuse protects against overloads, and the manual recommends verifying the breaker rating before connecting.
When switching voltage modes, the thermostat resets the schedule and temperature setpoints to default values. Users should re‑enter desired settings after a voltage change. The dual‑voltage feature also allows the thermostat to operate in a multi‑zone installation, where one zone runs on 120 VAC and another on 240 VAC, by connecting separate thermostat units to each circuit.
Safety checks include verifying grounding, securing the mounting plate, confirming the floor mat’s resistance. Acceptable ranges are 4–6 kΩ for 120 VAC mats and 2–4 kΩ for 240 VAC mats. Incorrect values trigger a fault mode error.
Installation Guidance
Secure the thermostat on a flat wall, 4‑6 in. above floor. Wire the sensor to the mat, ensuring a 1‑in. clearance from heated area. Connect the 14/3 or 12/3 cable to the panel, observe polarity, and install a GFCI breaker. Follow the wiring diagram for voltage mode.
Sensor Wire Placement
Before installing the SunTouch thermostat’s sensor wire, ensure the floor mat and heating cables are fully in place. The sensor should be affixed to the wall stud or a secure mounting surface, 4–6 in. above the floor to avoid contact with the heated area. Measure at least 1 in. into the heated zone from the wall to determine the exact placement. Mark the spot with a pencil, then drill a pilot hole that matches the sensor’s mounting screw diameter. Use a self‑drilling screw to secure the sensor, tightening it snugly but not overtightening to prevent damage. The sensor wire must run parallel to the floor heating cables, maintaining a minimum clearance of 2 in. from any high‑temperature surfaces to avoid overheating. Route the wire through the wall cavity, ensuring it does not kink or bend sharply; use a flexible conduit if the wire must cross a junction box. Connect the sensor wire to the thermostat’s sensor terminal, observing the correct polarity indicated on the terminal markings. After connection, test the sensor by placing a small heat source near the sensor area and verifying that the thermostat registers the temperature change. Finally, secure the thermostat housing to the wall with the supplied mounting hardware, double‑check all connections, and perform a functional test by setting a schedule and observing the thermostat’s response. This meticulous placement ensures accurate floor temperature readings and reliable operation of the SunTouch system. Use a 14/3 or 12/3 cable with insulation, label all wires clearly, and if a GFCI breaker is required, install it per local codes. Ensure the sensor’s mounting bracket is level to avoid skewed readings. The sensor wire should be insulated from the heating element’s voltage and routed away from any high‑temperature surfaces to prevent damage. After installation, monitor the thermostat for a few cycles to confirm stable operation before finalizing the setup
Electrical Wiring & Voltage
SunTouch thermostats are designed for both 120 VAC and 240 VAC floor‑heating systems. The 500675 model is dual‑voltage, allowing installation in regions that use either voltage level. To wire the unit, first turn off the main breaker and verify that the supply voltage matches the thermostat’s rating. For a 120 VAC installation, connect the line (L) and neutral (N) conductors to the thermostat’s L and N terminals, ensuring that the neutral is bonded to the building’s neutral bus. For 240 VAC, connect the two line conductors (L1 and L2) to the L1 and L2 terminals, and use a grounded neutral if the system requires it. The thermostat’s ground terminal should be connected to the building’s grounding electrode system. Use a 14‑AWG or 12‑AWG cable with insulated conductors, and secure all connections with wire nuts or crimped connectors rated for the voltage. If the local code requires a GFCI breaker, install the thermostat downstream of the breaker so that the GFCI protects the entire heating circuit. After wiring, double‑check all connections for tightness and correct polarity. The thermostat’s voltage selector switch should be set to match the supply voltage; the 500675’s selector is labeled “120/240” and must be in the correct position before power is restored. Once the power is turned back on, use the thermostat’s self‑test function to confirm that the voltage is correctly detected. The thermostat will display the voltage level on its LCD; a mismatch will trigger a fault indicator. Double‑check wiring energizing now!
Programming & Settings
Access the OPTIONS menu by pressing the button, hold for 1 s, then press again until “SSt” appears. Toggle automatic scheduling on/off, set start times, and adjust temperature limits. Use the HOLD/RETURN button to exit and save changes. Set the limit to your profile !
Options Menu & Schedule Adjustment
To adjust your SunTouch thermostat schedule, press the OPTIONS button and hold it for one second. The display will flash “SSt” indicating the schedule mode. Use the UP and DOWN arrows to navigate through the days of the week. When a day is highlighted, press the OPTIONS button again to enter the time setting screen. Here you can set the desired start time by rotating the dial or pressing the arrow keys. After confirming the start time, press the HOLD/RETURN button to return to the day list. Repeat this process for each day you wish to program. To change the target temperature for a particular day, first select that day, then press the OPTIONS button until the temperature display appears. Adjust the temperature using the arrow keys, and confirm with HOLD/RETURN. If you want to disable the automatic scheduling feature entirely, navigate to the “Auto‑Schedule” option, toggle it off, and save your settings. The thermostat will then operate in manual mode, heating whenever the floor temperature drops below the setpoint. Remember to keep the thermostat’s firmware updated to ensure optimal performance and compatibility with future features.
Operation & Energy Monitoring
The SunTouch thermostat displays real‑time heating status and logs cumulative heating hours. Use the display to view current mode, target temperature, and energy usage. The system records total heating time, helping estimate monthly costs. Adjust settings via the menu to optimize efficiency .
Normal Mode & Usage Tracking
In Normal Mode, the SunTouch thermostat continuously monitors floor temperature and automatically turns the heating system on or off to maintain the setpoint. The display shows current temperature, target setpoint, and the remaining time until the next scheduled change. Energy usage is tracked by recording the total heating hours stored in memory. This data can be accessed via the Options menu, where a cumulative log of heating time is displayed. By reviewing this log, users can calculate energy consumption and estimate monthly costs. The thermostat also offers a quick‑start feature that allows the system to heat immediately when the floor temperature drops below a user‑defined threshold, ensuring comfort without manual intervention. Additionally, the device supports dual‑voltage operation, allowing it to work with both 120 VAC and 240 VAC systems, which is reflected in the energy monitoring readouts. Users can export usage data to a USB drive or view it on a connected smart device through the SunTouch ConnectPlus app for remote monitoring and historical analysis. The combination of real‑time temperature control and detailed usage tracking provides an efficient and transparent heating experience. The thermostat’s firmware updates can be performed via the SunTouch ConnectPlus app, ensuring the latest features and bug fixes are available. Users are encouraged to regularly review the energy log to identify peak usage periods and adjust schedules accordingly. The system’s standby mode conserves energy when the floor temperature is within a comfortable range, further reducing operating costs.AAAAAAAAAAAAAAAAAAAAAAAAAAAAA