In stock at supplierSupplierECO Friendly Heating Systems UK
In stock at supplierEco Friendly Heating
Price
£47.83 ex. VAT£57.40 inc. VAT
Delivery · from ECO Friendly Heating Systems UK
The Heatmiser Slimline-E V3 is a smart, easy-to-use programmable thermostat designed to give you accurate control over electric underfloor heating systems. With a robust 16A switching capacity, flexible programming options and floor sensor control, it is a strong choice for bathrooms, kitchens, conservatories, living areas and other spaces where reliable temperature management matters.
If you are comparing controls, you can also read our Underfloor Heating Thermostats Guide for help choosing the right thermostat for your project. For wider planning, our Underfloor Heating Installation Guide and system selection guide can also help.
This thermostat is built for homeowners and installers who want dependable, programmable control without needing app connectivity. It is ideal where you want straightforward operation, dependable floor temperature sensing and a clean, modern wall-mounted design.
16A switching relay suitable for electric underfloor heating loads up to 3,680W
Flexible programming modes including 5/2 day, 7 day and 24-hour options
Self-learning Optimum Start to help the room reach temperature when you need it
Multiple sensing modes including floor sensor only, air plus floor, and remote air plus floor
Holiday Mode and frost protection for improved energy management
Large white backlit display with auto-dim function for simple everyday use
Keylock and temporary hold for added practicality in busy homes
The Slimline-E V3 offers three programming modes, helping you tailor your heating schedule to how you actually use the room:
5/2 day programming for weekday and weekend schedules
7 day programming for different settings each day
24-hour programming for a simple repeated daily routine
This flexibility makes it easier to reduce unnecessary heating time while still keeping floors warm when you need them most.
The built-in Optimum Start function learns how quickly your room heats up and calculates when to switch the system on. Instead of heating for a fixed, wasteful period, it aims to reach your chosen temperature at the right time. That means better comfort, less guesswork and potentially lower running costs.
If you are also planning system size and efficiency, our Underfloor Heating Calculator can help you plan your project more accurately.
A 3-metre NTC 10K floor sensor is included in the box. This allows accurate floor temperature monitoring and helps protect sensitive floor finishes from overheating where required. Depending on your setup, the thermostat can be configured in different ways:
Floor Sensor Only
Air and Floor Combination
Remote Air and Floor
This makes the Slimline-E V3 suitable for a wide range of heating mats, loose wire systems and other electric floor heating installations.
The Slimline-E V3 is designed to be easy to live with day to day. The slim profile looks neat on the wall, while the large backlit display keeps settings clear and easy to read. Helpful built-in functions include:
Holiday Mode for reduced heating while you are away
Adjustable frost protection during colder periods
Temporary temperature hold for quick comfort changes
Keylock facility to prevent accidental adjustments or tampering
Switch rating: 16 Amp / 3,680 Watts
Dimensions: 98mm (H) x 85mm (W) x 13mm (D after installation)
Mounting: Flush-mounted in a standard 35mm deep back box
Temperature range: Adjustable from 5°C to 35°C, with up to 45°C selectable
Sensor supplied: 3-metre NTC 10K floor sensor included
This thermostat is a strong option for customers who want:
Reliable programmable control for electric underfloor heating
A non-Wi-Fi thermostat with simple day-to-day use
Floor temperature sensing for better comfort and floor protection
A direct replacement for older Heatmiser Slimline-E models
Yes. It is specifically designed for electric underfloor heating systems and is a strong option where accurate floor temperature control and programmable comfort are important.
No. This is a programmable thermostat with local control, so it does not rely on WiFi, an app or cloud-based setup.
The thermostat has a 16A switching capacity, which makes it suitable for loads up to 3,680W.
Yes. A 3-metre NTC 10K floor sensor is included in the box for floor temperature monitoring and protection.
Optimum Start is a self-learning feature that works out how quickly the room heats up and switches the system on at the right time to reach the target temperature more efficiently.
It can help improve efficiency by using better scheduling, floor sensing and smarter start times, reducing unnecessary heating compared with less controlled systems.
Yes. It is a sensible option for replacing older Slimline-E models where you want similar straightforward control with updated features.
Need help choosing the right thermostat for your underfloor heating project?
Start with our Underfloor Heating Thermostats Guide, check likely sizing with the Underfloor Heating Calculator, or read the Installation Guide for wider project planning.
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