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Terma KTX 4 BLUE - Bluetooth Electric Heating Element Controller
Free Delivery To Mainland UK

Not sure what you need? Call our customer help line on 0330 058 6489 to discuss your needs.

Need help? Call us on:0330 058 6489

Terma KTX 4 BLUE - Bluetooth Electric Towel Rail Element Controller with Thermostat

This Works Well With:

Terma Dual Fuel T-Pieces Chrome - £7.95 (ex VAT £6.63) - (details)

Terma Dual Fuel T-Pieces White - £7.95 (ex VAT £6.63) - (details)

Terma Dual Fuel T-Pieces Black - £7.95 (ex VAT £6.63) - (details)

Terma Dual Fuel T-Pieces Silver - £7.95 (ex VAT £6.63) - (details)

Terma Elements TS 1 120W - £29.98 (ex VAT £24.98) - (details)

Terma Elements TS 1 200W - £29.98 (ex VAT £24.98) - (details)

Terma Elements TS 1 300W - £29.98 (ex VAT £24.98) - (details)

Terma Elements TS 1 400W - £29.98 (ex VAT £24.98) - (details)

Terma Elements TS 1 600W - £29.98 (ex VAT £24.98) - (details)

Terma Elements TS 1 800W - £29.98 (ex VAT £24.98) - (details)

Terma Elements TS 1 1000W - £29.98 (ex VAT £24.98) - (details)

Free Delivery on all UK mainland orders

Shipping: Allow 2-3 working days


towel rail elements The Terma KTX 4 BLUE heating element controller is the most advanced radiator heating element controller to date. It provides precise control over the temperature of your radiator with increments of 1 degree C when controlled via the Blue Line mobile phone application.

The heating element can be fully controlled through the BLUE-Line control mobile application via Bluetooth. The mobile application allows you to control both the temperature of the radiator (30-60 ° C) and the room temperature (15-30 ° C); program any number of 7-day schedules; program advanced timer.

The buttons on the controller’s housing allow you to set the operating temperature in a simplified way or run a simplified Timer (up to 4 hours). The device displays the currently set temperature level and indicates the status of the heating cycle or standby mode. The KTX 4 BLUE is designed to use with the TS 1 heating element. The unique feature of the KTX range of heating elements is the Terma-Split System. The Terma-Split connector makes it possible to disconnect the TS 1 from the controller head. More information on the TS 1 can be found on page 488. The KTX 4 BLUE is also equipped with actual heating time counter for energy consumption calculations.


• 5 temperature settings that range from 30°C to 60°C

• Dryer mode with the option to program both required power and heating cycle time (1h – 4h)

• Heating time meter for energy consumption calculation

• Available in 3 colours: white, chrome and black

• The KTX4 Blue is designed for use with the Terma-Split heating element, giving an option of disconnecting the controller from the heating element

• ANTIFREEZE function, protects your radiator in case the ambient temperature falls below 5 – 7°C

• Symmetrical casing allows you to install the element both on right or left hand sides.

 Do not use the heating element in heating systems where the water temperature exceeds 82° C.


The Terma KTX4 Blue equipped with Bluetooth® module allows:

• Wireless communication with the mobile application

• Programming any required number of heating cycles

• Controlling room temperature based on readings from an external temperature sensor (in development), which is an alternative to standard radiator temperature readings.


Download the app here:


Google Play App Store


 Google Play Terma App download

Itunes App Store


Download on App Store Terma Blue line

Remote Control:

 Any portable device, smartphone or tablet, with Bluetooth® can be used for remote control. BLUE-Line control mobile application for Android and iOS is available via Google Play® or Apple Store®. With one mobile device, it is possible to program and control any number of BLUE devices (radiator and heating elements) within range of the mobile device.

Intelligent Building Systems

In case of power loss the KTX4 remembers its settings making it suitable for connection with external timers and intelligent building systems.


The KTX 4 is equipped with a ‘frost’protection (ANTIFREEZE). It also has double protection against the element overheating as well as a safety feature that prevents damage in case of operation in a dry radiator. A device error or malfunction is identified by a display of error codes.


Equipped with an easy to read single digit LED display in blue. A version designed for permanent connection to the power supply, with a cover concealing the connection and mechanical switch on the housing, is available.


Available colours: chrome, white and black. Facia always comes in silver regardless of the housing colour. The heating element can also be offered in any RAL colour and Terma special colours (including brass and gold) subject to a minimum order of 100 pcs per colour. 


Dual Fuel Functionality when combined with a T-Piece


Power Supply: 230 V / 50 Hz
Element grzejny Terma Split I
Device Protection Class Class I
Radiator Connection G 1/2"
Ingress protection [IP]

IPx5: version with cable


120W = 315mm

200W = 285mm

300W = 310mm

400W = 345mm

600W = 375mm

800W = 485mm

1000W = 575mm


Customer Reviews

Based on 1 review
KTX 4 Blue

Does the job, but bluetooth range appears limited to the next room. And crashes easily. You have to shut the app down and re-start nearer the stat. Much better than the 3 which you have to get on hands and knees to see the digits.

Queensgate House, Bracknell, Berkshire, RG12 1RB   |  Company No. 10757797  |  Vat No. 245441516

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