tuya Mi-750 WiFi Smart Thermostat Instruction Manual

tuya Mi-750 WiFi Smart Thermostat Instruction Manual

Introduction

The Mi-750 is designed to control electrical underfloor heating systems indoors (heating mats, film heaters or heating cable sections). The thermostat maintains a comfort temperature set for the floor or room and contributes to energy-saving operation of your floor heating. The thermostat offers temperature control using two sensors: floor sensor (included in the scope of delivery) and air sensor (built-in). For heating control, either both temperature sensors can be selected (activated) simultaneously, or optionally only one of the two sensors.

The thermostat is mounted onto a wall (flush-mounting) in close proximity to installation wires of the heating system used.

Scope of delivery

Thermostat – 1 piece
Floor sensor – 1 piece
Instructions for use and installation – 1 piece

Special features

The thermostat Mi-750 enables to control your floor heating either directly from the device touch screen or by using the “Tuya Smart” app installed on a smartphone. The thermostat shall be connected to a smartphone via Wi-Fi.

• The WiFi network standards supported by the device are: IEEE 802.11. b/g/n 2.4 GHz.
• The operating system requirements for smartphones: Android 4 or higher, iOS 10.0 or higher.

Registration Tuya Smart app

App download

Scan the QR code with your smartphone or tablet or search for the keyword “Tuya Smart” in the App Store or the Google Play Store for the free app and download it.

https://apps.apple.com/us/app/tuya- smart/id1034649547https://play.google.com/store/apps/details?id=com.tuya.smart&hl=en

User account registration

The following steps are to be performed for user accont registration in the “Tuya Smart” app.

1. Run the “Tuya Smart” app on your smartphone and tap “Register” if you don’t have an account

2. Then perform the necessary steps in the app to create the user account by following the instructions on the The main steps are as follows.

3. Use the country or region that the system automatically identifies and displays or manually select a country or a region.
   Important: Aker registration, the country or region cannot be changed.

4. Enter an email address and tap “Get Verification Code”.

5. Enter the confirmation code that you will receive by

6. Now, the password settings Set a password. The password requires 6-20 characters, and must contain both letters and digits.

7. After you have assigned a password to protect your account and tap “Done”.

https://smartapp.tuya.com/tuyasmart

Important notes before installation

Read these instructions carefully before use and retain. If necessary, pass the instructions on to a subsequent user. The installation must be performed by a professional electrician in compliance with DIN-VDE norms and applicable national laws, rules and regulations. Otherwise the warranty invalidates. Switch off power from all wiring before ins talling, testing or replacing the thermostat. Only use electrical plastic wall mounting boxes for the thermostat installation.

Installation

Floor temperature sensor installation

The floor temperature sensor cable has to be placed into a separate conduit according to EN 61386-1.

It should be placed at heating level directly underneath the heating mat by chiselling out a channel in the subfloor. The sensor should be centrally positioned between two heating conductors, which is in the middle of a cable loop. Route the heating mat cold lead through the second corrugated tube. Do not cross the cold lead over or place it closer than about 2 cm to the mat heating wires. Thermostat installation requires a standard plastic wall mounting box with 230 V AC mains connection cable from the local wiring at the intended location. A fault-current circuit breaker (30 mA) has to be used. Double-check that the floor sensor is positioned in a corrugated tube (Ø16mm) and can be easily removed from; check this during installa tion of the tube and again before installation of the screed and floor covering respectively!

Connect the thermostat

Important!
We recommend to use the services of qualified specialists when installing the thermostat and heating system. The electrical connection and connection to the power supply must be performed by a professional electrician in compliance with the applicable national laws, rules and regulations. The installation instructions and wiring diagram do not replace the professional skills of the device installer. Disconnect your local wiring from the mains before connecting the thermostat or disconnecting the device to check or replace it.

Install the mounting box with suitable screw spacing of 60 mm and the intermediate junction box if necessary (e.g. if two or more heating mats are to be connected and controlled with one thermostat). Lead power supply cable, installation wires of the floor heating, and temperature sensor installation wire to the box. Energize the supply cable and find the phase wire and the neutral wire using voltmeter; mark these wires. Afterwards, de-energize the power supply cable.

Connect all required wiring to the thermostat using its terminals with screw fastening.

• The floor temperature sensor must be connected to the two terminals marked with NTC (polarity does not matter).

Important!

If the installation distance is shorter than the sensor installation wire (standard 3m), the sensor cable must be shortened accordingly.

• The supply voltage (230 V AC) is applied to terminal N and L, with the phase wire (detected by voltmeter) – to terminal L , and the neutral wire – to terminal N.
• The heating element installation wires are to be connected to terminals N LOAD and L LOAD ; the screening braid output (yellow-green wire) must be connected to the protective earthing (PE) line via an external terminal contact (not included in the scope of delivery).

Important!
In order to keep the thermal impact on the relevant device components low in the event of improper use under continuous load and to achieve maximum service life, it is recommended to switch (connect) a maximum load current of 13 A (2990 W).

Mounting the thermostat

1. Remove the front cover (part with display). Carefully press the latch on the upper side of the front cover using a thin slot screwdriver and gently pull the front cover off in your.
2. Make the electrical connection.
3. Insert the rear cover of the device into the wall mounting box and fasten with two screws, left and right at the same.
4. Insert the display into the frame and align the connector contacts on the rear with the connector receptacle on the rear
5. Carefully press the front cover with the frame against the rear cover (inserted in the flush-mounted box before) until the latch lock in Make sure that the front cover tightly adjoins the rear part of the thermostat.

Important!

Avoid damaging or bending the contacts of the connector during installation.

__

Thermostat installation for two or more heating mats

1. Electrical thermostat; power supply cable NYM 3 x 5 mm².
2. Corrugated tube for the temperature sensor (floor sensor) or the cold lead (both are not to be installed inside the same tube).
3. Flush-mounted junction box (if two or more heating’s mats are to be connected to the same thermostat, a separate flush-mounted junction box is required).

Display structure

Note:
When the device is switched on for the first time, the Wi-Fi signal starts flashing continuously until having connected successfully to your local Wi-Fi network (cf. settings F5 – Wi-Fi connection). If the device is connected to the Wi-Fi, the icon will continue to be displayed, but will stop flashing. If there is no access to the Wi-Fi network (e.g. reception disturbed, weak signal level), the icon will not be displayed.

Operation – basic functions

Switching ON/OFF

Tap the home button o and keep pressed for about 3 seconds to switch the thermostat on or off. When the device is switched off (stand-by), the display shows the information according to what has been selected in advanced settings F4, code 16. If no button is tapped for about 30 seconds, the screen will go blank (the display will be black). With tapping one of the input keys ˅ o ˄ the display is reactivated.

Note:
Each time the device is switched on, all the icons (see overview of display structure) appear on the display for a short moment.

__ Activate key lock

Switch to the display main screen and tap the ˄ button for about 3 seconds to activate the key lock (child lock). To disable the key lock, tap the ˄ button for another 3 seconds. The thermostat can also be locked or unlocked in standby mode.

Display sleep mode

If no button is tapped, the display will switch to sleep mode after about 25 seconds by dimming. With tapping one of the input keys ˅ o ˄ the sleep mode ends.

Note:
If the thermostat is on, the last active screen is displayed in sleep mode. When the device is in standby mode, the display shows the information according to what has been selected in advanced settings F4, code 16.

Select operation mode

Switch to the display main screen, tap the home button o and select one of the following operating modes:
Program – Comfort – Eco – Holiday.
Switch between the operating modes by repeatedly tapping the home button o.

Operating modes

Comfort mode

Using comfort mode, the thermostat permanently (24/7) maintains the desired temperature. The temperature can be selected with the ˄ and ˅ buttons. Do not confirm the selection with the o button, but wait a short moment until the temperature display changes from ST to RT or FT.
Temperature setting is possible in the range of +5 °C bis +35 °C. The default setting (factory setting) is 23 °C.

ECO mode

Using ECO mode, the thermostat permanently (24/7) maintains the desired temperature. The temperature can be selected with the ˄ and ˅ buttons. Do not confirm the selection with the o button, but wait a short moment until the temperature display changes from ST to RT or FT.

Temperature setting is possible in the range of +5 °C bis +35 °C. The default setting (factory setting) is 18 °C.

Program mode

Using program mode, the thermostat automatically controls the heating to the set temperature depending on the time and day of the week. The thermostat operates on a 4-phase schedule. A phase means a planned period of the day. According to the selected week profile (cf. advanced settings F4, code 05), four periods (events) with time and temperature can be programmed for all weekdays or a group of weekdays (cf. set- tings F2). Best solution for a daily routine as follows: waking up in the morning, going to work, coming back home and going to sleep. Temperature setting is possible in the range of +5 °C bis +40 °C.

Using ˄ and ˅ buttons, the temperature can be manually adjusted from the running mode at any time from the running mode. Confirm the selection with the o button or wait a short moment until the temperature display changes from ST to RT or FT. As a result, the thermostat switches to Temporary mode. The changed temperature setting is only applied temporarily for the running heating period (event) but will not be saved in the settings. With the beginning of the following period, the thermostat returns to set week program.

Holiday mode

This operating mode allows to set the floor heating to economy mode during planned absence (e.g. vacation) in order to save energy. The thermostat permanently (24/7) controls the heating for the duration of absence to the set economy temperature maintains it permanently (around the clock). For setting the duration of absence (number of days of absence) cf. settings F4, code 11. The temperature can be selected with the ˄ and ˅ buttons. Do not confirm the selection with the o button, but wait a short moment until the temperature display changes from ST to RT or FT. If the absence period is expired, the thermostat automatically switches to the program mode, regardless of which operating mode has been previously selected. Temperature setting is possible in the range of +5 °C bis +20 °C.
The default setting (factory setting) is 10 °C.

Settings

Tap the home button o and keep pressed for about 3 seconds to switch the thermostat off. Then tap the ˄ and ˅ button at the same time and hold them down until F1 appears on the display. Using the ˄ and ˅ buttons, you can select between F1, F2, F3, F4, F5.

Note:
If in F1 and F2 settings there is no request made for a few seconds, the thermostat will automatically exit the settings and return to the main screen. The settings made up to this point will be saved. Return to the settings again if necessary.

4 periods (events) for each weekday
F3| Operation time reading| Read operation time day, month, year
F4| Advanced settings| Effect advanced settings
F5| WiFi connection| 000: no reset

001: Reset device and pairing (WiFi connection) using EZ mode

002: Reset device and pairing (WiFi

connection) using AP mode

__ F1 – Date and time setting

Select F1 and tap o. Use the ˄ and ˅ buttons to select the day of the week first and then the time (hours, minutes). Confirm both setting each with tapping o. As soon as the “ Minutes ” have been confirmed with o you will automatically return to the main screen. You can exit the settings at any time by long tapping o.

F2 – Program mode setting

Note:

You can choose from two different week profiles, cf. advanced settings F4, code 05 . Either 5 – 1 – 1 = Mon to Fri – Sat – Sun, or 7 = each weekday individually, Mon – Tue – Wed – Thu – Fri – Sat – Sun.

__ Select F2 and tap o. Use the ˄ and ˅ buttons to select the day of the week and the period (event). Tap o. Now use the ˄ and ˅ buttons to set the time first and confirm with o. Next, set the temperature using the ˄ and ˅ buttons and confirm with o. Use the ˄ and ˅ buttons

to move to the next period and day of the week respectively. Proceed with the settings for all other days and periods in the same way. After you have programmed all the days of the week, long tap o to exit the settings. Otherwise, the thermostat will automatically switch to the main screen after 5 seconds.

Default settings (factory settings) for Program mode:

F3 – Operation time reading

Select F3 and tap o. Using the ˄ and ˅ buttons, you can read the operating time for day, month and year. To exit the settings, tap o.

F4 – Advanced settings

Note:
Changes to the advanced settings should only be performed by a qualified person.

Select F4 and tap o to move to the first parameter (01 is shown on the display). Using the ˄ and ˅ buttons allow to adjust the value now. Tap o to move to the next parameter. To exit the advanced settings, long tap o.

Example:

Note:
The various parameters (cf. codes 01 – 18) of the advanced settings are arranged in a fixed order. You can only switch to the next parameter, but not return to a previous one. To do this, you must either exit the advanced settings and select F4 again or tap o repeatedly until you reach the corres ponding parameter again (code 18 is followed by code 01 ff. again).

Note:
The parameters marked with *_)_** in the following table can only be set directly on the thermostat and cannot be adjusted via the “Tuya Smart” app.

Code| Parameter| Factory setting| Possible settings| Comment
---|---|---|---|---
01| Sensor selection| 01| 01: Room sensor with floor temperature limitation 02: Room sensor

03: Floor sensor

| The device offers control of the underfloor heating using a floor and a room temperature sensor. Optionally, either only one of the two sensors can be activated or both sensors can be selected at the same time. In this case, the room sensor controls the heating depending on the set maximum floor temperature (cf. code 04), which is used for limitation.
02| Room sensor calibration| 0 °C| -5 °C … +5 °C| Allows you to calibrate the room sensor (integrated in the device) if the measured temperature differs from the actual room temperature. The usual self-heating of the device during its normal operation can affect the temperature measurement, as well as the positioning of the thermostat, e.g. near other heat sources, windows, doors.
03| Floor sensor calibration| 0 °C| -5 °C … +5 °C| Allows you to calibrate the floor sensor if the measured temperature differs from the actual floor temperature.
04| Floor temperature limitation| 35 °C| +5 °C … +60 °C| Allows you to set a maximum floor temperature as the upper temperature limit. This is particularly beneficial when, for example, laminate or click vinyl flooring is to be protected from excessively high temperatures.
05| Week profile| 5-1-1| 5-1-1,

7

| According to the selected week profile, either all weekdays can be programmed individually or the working days are combined as one group.

5-1-1 = Mon to Fri (as a group) – Sat – Sun / 7 = Mon – Tue – Wed – Thu – Fri – Sat – Sun (each weekday individually). Note: Relevant only for Program mode.

06| Adaptive start (self-learning mode)| Off (no)| On (YES),

Off (no)

| By continuously analyzing the previous heating characteristics, the thermostat automatically calculates the required turn-on time (preheating time) so that the set temperature can be achieved in time until the programmed time. If this function is OFF, the thermostat will turn on the heating exactly at the programmed time.

Note: Relevant only for Program mode.

07 *)| Adaptive start time (preheating time)| 20 Min.| 0-40 Min.| When the adaptive start function (cf. code 06) is activated for the first time, the heating is switched on earlier according to the preheating time selected under this item. Through the continuous analysis described under code 06, the preheating time for future heating periods will be adapted step by step to the requirements.
08| Open window detection| Off (OFF)| On (on), Off (OFF)| The thermostat permanently monitors the room temperature. If it has dropped by more than 5 degrees within 15 minutes, the thermostat assumes that window is open and turns off the heating for 30 minutes to save energy. After this time, the heating control continues in the last active operating mode. If you change the operating mode during the 30 minutes, the open window detection will be cancelled immediately and the symbol on the display goes out.

Note: Open window detection is active even if only the floor sensor (cf. code 01, setting 03) has been activated.

09| Floor sensor type| 10 kOhm| 3, 5, 6.8, 10, 12,

15, 20, 22, 33,

47 kOhm

| The device also supports other types of floor temperature sensors. This setting allows you to specify the type of floor sensor by selecting the appropriate nominal resistance.
10| Anti-freezing mode| On (YES)| On (YES),

Off (no)

| Used to keep the temperature above the freeze point when a room is is not used for a longer period of time. This prevents e.g. pipes from freezing. The thermostat keeps the temperature above +5 °C. It means, at ≤ +5 °C the thermostat switches heating on, and switches off when +7 °C is reached. If you have activated this function by selecting “ On (YES) ” , it will be active even if the thermostat is in stand-by.
11 *)| Holiday time| 1 day (01)| 1-99 days| Setting of time of absence for the operation of the heating system in holiday mode.
12| Switching delay| 1 °C| 0.5 °C, 1 °C, 2 °C,

3 °C

| Switching delay means that the thermostat does not switch the heating on or off when exactly the set target temperature is reached, but earlier or later by the selected switching tolerance value.

Example: Set temperature 26 °C, switching delay 1 °C, the thermostat switches the heating on at ≤ 25 °C and off at ≥ 27 °C.

The lower the set value for the switching delay, the more circuits of the controller.

The larger the set value, the less accurate the temperature control.

13 )| Display accuracy| 0.5 °C| 0.5 °C, 0.1 °C| Setting at which degree of accuracy the temperature is to be shown on the display. Either 0.1 °C steps (e.g. 23.1 °C, 23.2 °C) or 0.5 °C steps (e.g. 23.0 °C, 23.5 °C).
14 )| Temperature input steps| 0.5 °C| 0.1 °C, 0.5 °C, 1 °C| Setting in which °C steps the set temperature can be adjusted.
15| Reset| No (no)| Yes (YES),

No (no)

| Allows to reset the device to factory settings.

Note: If “YES” is selected, long tap o to confirm until the main screen appears.

The device is now reset.

16 *)| Display indication when device is switched off| 02| 01: Displays “ OFF ”

02: Temperature is displayed

| Allows you to select the information to be shown on the display when the device is switched off.
17| Temperature unit| °C| °C, °F| Selection of the temperature unit, Celsius oder Fahrenheit.
18 *)| Device status at restart (after the device was disconnected from the power supply)| 1| 1: Return to previous operating state 2: Device OFF

3: Device ON

| Setting to which status the device is to be set after the power supply has been restored (e.g. if a power failure occured).

1: The device returns to the previous operating state (from before the power interruption). If the thermostat was switched off, it remains switched off. If the device was turned on, it returns to the previous active operating mode.

2: The device is or remains switched off.

3: The device is switched on and continues to operate in the previous active operating mode.

F5 – WiFi connection

WiFi connection guidelines:

• WiFi network standards supported by the device: IEEE 11. b/g/n 2.4 GHz.
• Position the antennas of the WiFi router according to the manufacturer‘s recommendations in order to achieve the maximum WiFi signal level at the place where the thermostat is
• The number of thermostats connected to the home network at the same time depends on the type of your
• If the WiFi signal level of your home network at the place of installation is interfered by other WiFi networks or sources of interference in the 2.4 GHz range, we recommend changing the WiFi channel to a less busy one, eliminating the source of interference, changing the position of the router, or using equipment to expand the radio coverage area (access points and repeaters).
• When installing thermostats in rooms of a large area, complex configuration, or in case of problems with setting up a WiFi connection, it is recommended to contact a specialist in setting up WiFi

Note:

The Wi-Fi signal strength, as well as the occupied Wi-Fi channels, can be checked e.g. using a suitable smartphone App (available for iOS and Android devices) by holding the smartphone next to the place where the thermostat is installed. Also most routers offer the ability to analyse the signal strength of connected WiFi devices. If the signal level is less than desired, reposition the router, or use equipment to increase the coverage of the WiFi network (access point, repeater, etc.). WiFi signal propagation is affected by concrete floors, metal objects (cabinets, boxes, mirrors, etc.), as well as sources of interference (e.g. microwave ovens). WiFi access points installed in adjacent rooms can also be a source of radio interference. Since the thermostat is deepened into the wall, the perceived WiFi signal level may be lower than that shown by a smartphone.

Adding a device
To be able to program and operate the thermostat with the “Tuya Smart” app , you must first add the device to the app and connect it to your smartphone or tablet via WiFi. There are two options available:
“Automatic Add” method via Bluetooth and “Manual Add” method. The “Automatic Add” method is recommended. The manual method is available as an alternative in case the automatic connection has not been successful.

Method 1: Automatic Add

1. Make sure that your WiFi is switched on, is in workable condition, and is active on the 4 GHz frequency band.
2. Activate Bluetooth on your end device
3. Log in to your “Tuya Smart” user account with your login
4. The thermostat will be automatically identified by your smartphone and displayed in the details.
5. Tap “Add device”.
6. Enter the network name and password or select a WiFi network which has already been Then tap “Next”.
7. The thermostat will now be added automatically.
8. After the device has been added successfully, tap “Done”.

Note:
Using “ Automatic Add ” method does not require to open settings F5. Proceed as follows if the device is not automatically identified and displayed in the app. Tap the home button o and keep pressed for about 3 seconds to switch the thermostat off. Then tap the ˄ and ˅ button at the same time and hold them down until F1 appears on the display. Select F5 using the ˄ and ˅ buttons. Select 001 in the following settings and confirm with tapping o . Wait a moment. The WiFi signal __   on the display of the thermostat starts flashing quickly. Open the “Tuya Smart” app. On the main screen, tap the button     in the upper right corner, then tap “ Add Device ” .

Method 2: Manual Add

Note:
The thermostat supports two pairing modes, EZ mode and AP mode.

EZ mode:
Select F5 using the ˄ and ˅ buttons. Select 001 in the following settings and confirm with tapping o. Wait a moment. The WiFi signal on the display of the thermostat starts flashing quickly. Open the “Tuya Smart” app. On the main screen, tap the button  __in the upper right corner, then tap “Add Device”. Next select “Small household appliances” as the device type first (left menu), then “Thermostat (Wi-Fi)” in the “HVAC” group of the right selection menu. Enter the network name and password or select a WiFi network which has already been added and tap “Next”.

Tap “Confirm that the signal flashes quickly” and then tap “Flashing quickly ” in the subsequent view. The connection process starts. After the device has been added successfully, tap “Done”.

AP mode:
Select F5 using the ˄ and ˅ buttons. Select 002 in the following settings and confirm with tapping o. Wait a moment. The WiFi signal on the display of the thermostat starts flashing slowly. Open the “Tuya Smart” app. On the main screen, tap the button in the upper right corner, then tap “Add Device”. Next select “Small household appliances” as the device type first (left menu), then “Thermostat (Wi-Fi)” in the “HVAC” group of the right selection menu. Enter the network name and password or select a WiFi network which has already been added and tap “Next”.
Tap “Confirm that the signal flashes quickly” and then tap “Flashing slowly ” in the subsequent view. Tap on “Connect now”. The WiFi settings of your smartphone will now be opened automatically. Select the WiFi network (hotspot) “Smartlife-**”**. The connection process starts. After the device has been added successfully, tap “Done”.

Alarm indication and troubleshooting

Check thermostat or floor temperature sensor. The device must not be put into operation again until the fault has been rectified.

The following safety instructions must be observed.

| installed in the device.
Er2| Short circuit or defect of the external floor
| temperature sensor or
| breakage of the sensor
| cable.

Important!
Working on the thermostat including the external floor temperature sensor must only be performed by a professional electrician. The electrical connection and connection to the power supply as well as disconnection of the device from power supply must be performed by a professional elec trician. Disconnect your local wiring from the mains before installing the thermostat or disconnecting from power supply to check or replace the device or the external floor temperature sensor.

Note:
In case of an interruption of the power supply (e.g. in the event of a power failure or if the thermostat has been disconnected from power supply to check it), the following settings will be retained for 30 days :

• F1 – Date and time
• F2 – Program mode settings
• F4 – Advanced settings
• Last active operating mode
• Set temperature

All other settings will be lost and have to be made new.

Tuya Smart APP navigation

Reservation
All information given are believed to be reliable and correct and correspond to the current state of our knowledge. Modifications,
mistakes and printing errors do not justify claims for compensation. Liability is governed exclusively by the general terms and conditions. Specifications are subject to change without prior notice.

Technical data

Thermostat Mi-750

47 kOhm

*) In order to keep the thermal impact on the relevant device components low in the event of improper use under continuous load and to achieve maximum service life, it is recommended to switch (connect) a maximum load current of 13 A (2990 W).

Floor temperature sensor NTC 10 kOhm

Claims

In case of a claim during the warranty period please contact the seller. The sensor will need to be sent back together with the thermostat for processing a claim.

Warranty

The manufacturer guarantees the conformity of the thermostat with the design description, assuming compliance with the installation and operating instructions.
Warranty period – 2 years from date of purchase.

In case of a defect during guarantee period caused by a manufacturing defect, the customer has the right to supplementary performance. The warranty does not cover any defects due to inadequate handling, damages through a third party, wrong installation (not following the manual) or its consequential damages. Please keep your sales receipt.

For any warranty claims you have to show your sales receipt as well as completed test protocol/guarantee card.

Guarantee card ****

Completed guarantee card/test protocol is necessary for warranty claims.

Thermostat
(Type name, Article number)

CLIENT
Name
Telephone    _
Street
E-Mail  
_Postal code, city   _
_Country
Client’s signature
Date of purchase 20 ____

INSTALLAER

Name
Telephone    _
_Company name    _
_E-Mail  Postal code, city   _
_Date of installation  20 __
Installer’s signature __

The thermostat Mi-750 has passed all the tests successfully.

FLOOR TEMPERATURE SENSOR

PERSONAL SETTINGS

Here you can record your personal settings for the Program Mode.

NOTES

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