Wi-Fi thermostat

By means of the COMPUTHERM S300 type Wi-Fi thermostat the connected apparatus (e.g. gas boiler) can be controlled via the Internet and its operation can be checked by your cell phone or tablet.
This product is an excellent choice for those who wish to control an electric device installed in their home via the Internet. In addition to providing convenience, this reasonably priced apparatus may contribute to reducing costs. A heating system controlled by an existing thermostat and complemented with a COMPUTHERM S300 Wi-Fi thermostat can be made remotely controllable by means of a smartphone via the Internet.
This product is especially useful when you do not use your flat or house according to a predetermined schedule, you leave your home for an uncertain period of time or you wish to control or check the heating of your holiday home remotely during the heating season.
Within the load limits, the remote control of any mains powered electrical device (e.g. watering pump, refrigerator, etc.) can be solved easily with the COMPUTHERM S300 thermostat, depending on the temperature or humidity. You can turn on/off the devices connected to the product remotely and scheduled power on/off is also possible.

  • Supply voltage for the thermostat: 90-230 V AC; 50/60 Hz
  • Standby power consumption: 0.1 W
  • Temperature measuring range: -20 °C – +70 °C
  • Temperature measurement accuracy: +/- 0.5 °C
  • Adjustable measuring range: -20 °C – +70 °C
  • Humidity measuring range: 0 – 100 % RH
  • Humidity measurement accuracy: +/- 2 % RH
  • Adjustable humidity range: 0 – 100 % RH
  • Switch sensitivity: +/- 1 °C (temperature); 1 % RH (humidity)
  • Output voltage of the thermostat: 90-230 V AC (identical with the input voltage)
  • Output loadability of the thermostat: 16 A (3 A inductive)
  • Operating frequency: Wi-Fi (b/g/n) 2.4 GHz

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What purpose can a COMPUTHERM S300 Wi-Fi thermostat be used for?

By means of a COMPUTHERM S300 Wi-Fi thermostat you can control the device connected thereto (e.g. a boiler) and can inspect its operation trough your cell phone or tablet via the Internet. COMPUTHERM S300 thermostat offers an excellent solution for those who wish to control an electrical device installed their home remotely via the Internet.

An existing heating system controlled by a thermostat and supplemented with a COMPUTHERM S300 Wi-Fi thermostat can be made remotely controllable with the help of a smart phone via the Internet. This product is especially useful when you do not use your flat or house according to a predefined schedule, you leave your home for an uncertain period of time during the heating season or you intend to use your holiday home during the heating season as well.

Besides, below the maximum loadability limit, with the COMPUTHERM S300 thermostat any other maims-powered electrical devices (e.g. watering pump, refrigerator, etc.) that can be turned on and off by interrupting and resuming power supply can easily be equipped with remote control.

Is this product suitable for independent heating control?

The COMPUTHERM S300 Wi-Fi thermostat is not really suitable for independent heating control but it is particularly suitable for making an existing central heating system equipped with a thermostat remote controllable. For more detailed information please refer to Chapter 5 of the Instruction Manual.

How S300 will reduce the total amount of your bill?

Due to its remote controllability S300 can save energy for you because this way you can remotely turn off the device to be controlled when you are away then turn it on later.

Can S300 be used for air-conditioning equipment?

Yes, this product is able to control air-conditioning equipment as well, provided that it is controllable, by interrupting and resuming 230 V power supply.

Can S300 be used only for heating control?

No, the apparatus is able to control cooling and watering systems or any device that can be operated by interrupting and resuming power supply only. You can switch between different modes in the Settings menu of the thermostat.

What type of battery / mains supply is required for the operation of S300?

Batteries are not required for the operation of S300. 230 V mains supply is required for the operation of the socket.

Where can you buy it?

Search  this  product  at  our  reseller  partners.  The  list  of  our  reseller  partner  is  available  at  the following link:

Where you can find the Instruction Manual of the appliance?

Instructions   for   installing   and   operating   S300   are   available   at   the   following   website:

From where can you download mobile application of S300?

If you use an Android operating system you can download the application from Google Play Store. If you use iOS operating system you can download the application from iTunes Store. The name of the application is COMPUTHERM S Series.

How many S300 appliances can be controlled from a single telephone?

The number of the appliances is unlimited. Every commissioned S300 appliance can be added to your profile and can be controlled from your phone.

Will several S300 thermostats used in the same flat disturb each other’s operation?

No. Each thermostat is connected to the local Wi-Fi network separately and this solution guarantees reliable and trouble-free operation of the appliances.

Is it absolutely necessary to have a Wi-Fi connection with Internet access for using S300?

A Wi-Fi connection with Internet access is required for commissioning and setting the appliance but then the appliance continues to operate without Internet and a Wi-Fi connection according to the settings defined. Besides, while the thermostat is not accessible from the Internet, you can manually turn on and off it with a button on the appliance. Despite this, a Wi-Fi connection with Internet access is recommended for convenient use of the appliance.

How can you connect the appliance?

For   more   detailed   information   please   refer   to   the   Instruction   Manual   of   the   appliance (

How can you restart appliance S300?

To restart the appliance pull out the plug of the appliance from the socket then, after 10 seconds have elapsed, connect it again to the mains power source.

Where should the thermostat and its temperature sensor be located?

It is expedient to locate the temperature sensor where you stay regularly or a long period of time so that the sensor is oriented in the direction of the natural ventilation of the room but is not exposed to draught or extreme heat (e.g. sunlight, refrigerator, chimney, etc.). Its optimal location is at a height of 1.5 m from the floor level.

When choosing the location of the main unit you should remember that bulky metal objects (e.g. a boiler, buffer tank, etc.) and metal building structures may have an adverse effect on propagation of radio waves. If it is possible, in order to ensure trouble-free RF connection, we recommend that you install the main unit at a height of 1.5 to 2 m and at a distance of 1 to 2 m from the boiler or other bulky metal constructions. We recommend that you check reliability of Wi-Fi connection at the place selected before installing the main unit. Do not install the main unit under the housing of the boiler or near hot pipes because it may damage the parts of the device or compromise Wi-Fi connection. We also recommend that the power is preferably supplied to the main unit from a socket other than that of the boiler (and from another phase, if it is possible), and line power must not be supplied to the main unit from the boiler on any account.  To avoid electric shock, entrust a specialist with connecting the main unit to the boiler!

Can several floor temperature sensors be connected to a single appliance simultaneously?

No, only one floor temperature sensor can be connected to a single appliance.

What should you do if the signal of your Wi-Fi router is weak and thus S300 is outside the range of the router?

If it is possible, put the router closer to your S300 appliance. Another option is to place a Wi-Fi signal booster between the router and S300 to extend the range of the router.

What should you do if you encounter a problem related to the Wi-Fi network?

If the appliance cannot be controlled via the Internet because the application indicates that the appliance is inaccessible and does not respond to the modifications then the connection between the appliance and the web interface has been interrupted. This situation may be due to several reasons. The problem is most probably caused by the Wi-Fi router being used. It is expedient to restart the routers from time to time by interrupting and restoring power supply. In most of the cases this type of problems is solved by restarting the router. If the appliance is still inaccessible at the front end after a few minutes have elapsed then it is recommended that the appliance is reconnected to the Wi-Fi network according to Chapter 4.2 of the Instruction Manual. If the connection is successful but the appliance is still inaccessible then it is recommended that the router is set to factory default, because it may occur that the device cannot be connected to the Internet because of some settings.

While the thermostat is inaccessible via the Internet you can turn it ON/OFF manually by pressing the button of the thermostat.

How does this product continue to function after a power outage?

The appliance does not work without power supply but it memorizes the settings and resumes operation without any intervention after the power supply is restored (the power outage is eliminated). Please check – and modify if required – the settings of S300 Wi-Fi plug according to the needs and specify its position to be set after the power outage is eliminated and power supply is restored  (turned  on/off,  last  previous  condition;  see  Point  “f”  in  Chapter  5  of  the  Instruction Manual).

How can default setting of the appliance be restored (reset)?

Press and hold the button located on the side of the product for 3 – 5 seconds. Then the product is set back to factory default setting.