SDM6 WiFi Smart Thermostat with Ring Display

Overview

The SunAura SDM6 is a wall-mounted WiFi smart thermostat built around a distinctive circular LCD dial. The large outer ring reads the measured room temperature, while a smaller inner readout shows the set target temperature, so the heating state is readable at a glance from across the room. Three equal square keys — M, up (▲) and down (▼) — sit on the side of the slim 86×86 mm body, giving reliable mechanical control that stays easy to use even when the screen is dim or your hands are full.

The SDM6 is offered in two wiring versions to match the heating source. The 16 A electric version (L / N / N1 / L1 terminals, with an optional external floor probe) directly switches underfloor heating mats, heating cables, heating film and electric radiator loads. The 3 A dry-contact version (L / N / NO / NC) closes a clean loop for wall-hung gas boilers, water heating circuits and thermal actuator valves. One dial design covers electric, hydronic and boiler heating — simplify your stock, your specification list and your installer training.

Beyond the dial, the SDM6 connects to your home WiFi and a Tuya-compatible app for remote temperature control, weekly scheduling and voice control. It is built around a flame-retardant housing, a child lock, power-off memory and NTC sensing with ±1 °C accuracy. The SDM6 is manufactured by SunAura Thermal at our Qingdao factory, operating with ISO-style quality management and in-line testing on every thermostat batch, supplying heating controls to distributors and OEM partners in 50+ countries since 2008.

Key Features

• Circular ring LCD — the large outer ring shows measured ROOM TEMP, the smaller inner readout shows the SET target, with °C labels on both so room temperature and target temperature are never confused.
• Side physical keys (M / ▲ / ▼) — three equal square buttons on the side edge provide durable, tactile control; no flat glass icons to hunt for in the dark.
• Two load versions, one design — 16 A resistive output for electric heating, or 3 A dry contact (NO/NC) for wall-hung boilers and thermal actuators.
• NTC sensor, ±1 °C accuracy — stable room sensing with a 5–60 °C setting range and 0–50 °C display range.
• WiFi remote control — full temperature, mode and schedule operation through a Tuya-compatible app on iOS and Android.
• Weekly programming — six weekday periods plus two rest-day periods, each with its own target temperature; 5+2, 6+1 or 7-day schedule layouts selectable in the app.
• Child lock — an on-screen lock icon and app-side switch prevent children or guests from accidentally changing the heating settings.
• Power-off memory — user settings and the active programme are retained when power is cut, so the SDM6 resumes automatically after an outage.
• Flame-retardant housing — a fire-safe, IP20-rated enclosure built for safe continuous wall mounting.
• Slim 86×86 mm body — standard wall-box footprint, about 14 mm deep, in grey and white finishes to suit any room.

Display & Icon Guide

The SDM6 ring screen communicates the full heating state at a glance. The large outer ring readout is the measured ROOM TEMP, labelled in °C; the smaller inner readout next to SET is your chosen target temperature. Alongside the dial you will see the week icon (MON–SUN) for the current day, the time display in 24-hour format, a home icon for home mode, a weather/status icon, a child-lock hand icon when locking is active, and a heating-active waves icon that lights while the output is energised. Because room temperature and set temperature are shown in distinct sizes and positions, it is impossible to mistake one for the other.

Physically the SDM6 measures 86 × 86 × 14 mm on the standard European 86-box grid, in a choice of grey or white fascia. It runs from AC 90–240 V, 50/60 Hz, and is rated for installation in an ambient range of -5 °C to 50 °C.

The weekly programme is set in the app (not on the wall), and ships pre-set to a comfortable 22 °C, fully adjustable:

• Weekday (six periods): 06:00 / 08:00 / 11:30 / 12:30 / 17:00 / 22:00 — each period with its own independent target temperature.
• Rest day (two periods): 08:00 and 23:00 — a relaxed weekend and holiday schedule.

Technical Specifications

Applications

The SDM6 is a universal control for hydronic and electric heating across homes and light commercial spaces:

• Electric underfloor heating — heating cable loops, underfloor mats and graphene / electrothermal film beneath tile, wood, laminate and LVT floors (16 A version).
• Wall-hung gas / condensing boilers — the 3 A dry contact switches the boiler call-for-heating loop (NO/NC) for radiator and underfloor water systems.
• Water heating manifolds & thermal actuators — the NO/NC terminals drive normally-open and normally-closed zone actuators on hydronic manifolds.
• Heating panels & infrared heaters — wall panels, decorative heating paintings and convection heaters within the rated load.
• Radiator retrofits & offices — standard 86 mm wall-box fit for living rooms, bedrooms, hotels, offices and commercial showrooms.

Installation

1. Power off and prepare the wall box — isolate the supply, then mount the backplate on the standard 86 mm wall box; fix with the provided screws.
2. Wire the terminals — connect mains L and N, then the load: N1 / L1 for the 16 A electric heating output, or the NO / NC dry-contact pair for the 3 A boiler / actuator loop. Add the optional NTC external probe when floor limiting is required.
3. Tidy and close up — fold the wires neatly into the box, press the fascia onto the backplate until it clicks, then restore power.
4. Pair and commission — bring the SDM6 online with the Tuya-compatible app on a 2.4 GHz WiFi network, set your weekly programme and confirm the correct version (16 A electric or 3 A boiler) for the connected load.

The SDM6 must be installed by a qualified electrician, and the connected load must never exceed the rated output of the chosen version. A dedicated wiring diagram ships with every order, and our engineers are available by WhatsApp for remote commissioning support.

Compatibility with SunAura Heating Systems

The SDM6 is the natural control partner across the SunAura heating range. For electric systems it pairs with our heating film, underfloor mats and double-conductor heating cables; for hydronic systems it pairs with wall-hung boilers, radiator panels and manifold actuator zones. When you order film, mat, cable or a boiler-based system from SunAura, we can pre-configure the SDM6’s temperature limits, floor-sensor setting and schedule defaults to match your exact build-up, and supply the complete package — heater, thermostat and accessories — from a single factory source under one warranty. Distributors and OEM customers can also request private-label branding, grey or white fascia options, custom programmes and tailored packaging.

Quality, Certification & Support

SunAura Thermal has manufactured heating controls and electric heating products since 2008 from our Qingdao factory, operating with ISO-style quality management and in-line testing on every thermostat batch. The SDM6 is CE and IP20 rated, built with flame-retardant housing material, and backed by a 2-year warranty. We support distributors and OEM customers with private-label branding, custom weekly programmes, packaging design and drop-ship logistics to more than 50 countries, with direct after-sales help by WhatsApp in English, German, French and Chinese.

FAQ

1. How do I read the circular ring display?

The large outer ring readout is the measured room temperature (labelled ROOM TEMP in °C). The smaller inner readout next to SET is the target temperature you have chosen. The icons around the dial show the day of week, the clock, home mode, weather status, the child-lock state and whether heating is currently on — so one glance tells you both how warm the room is and what you are aiming for.

2. How do I operate the side buttons?

Three equal square keys sit on the side edge: press M to cycle between modes and enter settings, and use ▲ / ▼ to raise or lower the set temperature. The same functions are available in the app, so the side keys are mainly for quick on-the-wall adjustments without opening your phone.

3. Which version do I need — 16 A or 3 A?

Choose the 16 A version (L / N / N1 / L1) when the thermostat directly switches an electric heating load such as underfloor cable, mat or heating film. Choose the 3 A version (L / N / NO / NC dry contact) when the thermostat only makes or breaks a call-for-heating loop for a wall-hung boiler or manifold actuator. Confirm the version at ordering — the two versions are not interchangeable after wiring.

4. How do I pair the SDM6 with the app?

Install the Tuya-compatible app on your iOS or Android phone, add a new device, and follow the pairing prompts on a 2.4 GHz WiFi network. Once online you can set the temperature, switch modes, program the weekly schedule and enable voice control — all remotely.

5. What happens to my settings during a power cut?

The SDM6 has power-off memory: your set temperature, mode and weekly programme are stored in non-volatile memory. When power returns, the thermostat resumes the last schedule automatically — no re-programming needed.

6. Do I need an external sensor?

An external NTC probe is optional. It is recommended for electric underfloor heating when you want floor temperature limiting or floor-sensing control; in that case connect the probe to the marked terminals and select the external sensor in the settings. For boiler and room-only control, the internal sensor is sufficient.

7. How does the weekly programming work?

You set the schedule in the app: six independent time-and-temperature periods for weekdays and two for rest days, pre-set to a comfortable 22 °C. You can switch the calendar layout between 5+2, 6+1 or a full 7-day week, and the SDM6 then follows the programme automatically.

8. What is the warranty and after-sales support?

Every SDM6 includes a 2-year warranty and direct after-sales support from SunAura — spare parts, configuration help and commissioning guidance by WhatsApp, in English, German, French and Chinese.

Looking for a smart thermostat with ring display that makes room temperature readable from across the room? The SunAura SDM6 is a circular dial WiFi thermostat for boiler and underfloor use, offered as either a 16 A resistive version for electric heating or a 3 A NO/NC dry contact WiFi thermostat for wall-hung boiler and manifold actuator loops. The factory notes below cover ordering, version selection and the questions installers most often ask before placing a carton order.

How to Buy from SunAura Factory

SunAura Thermal supplies the SDM6 directly from our Qingdao factory to installers, distributors and project buyers in 50+ countries. Order a single unit for a renovation, a carton for your trade counter or a container of private-labelled thermostats for your own brand. Wholesale price breaks, bulk discounts and free samples for serious trade customers are available — tell us whether you need the 16 A electric version (L/N/N1/L1 with external probe) or the 3 A dry-contact version (L/N/NO/NC), plus the quantity and destination port, and we will reply with a same-day EXW or FOB quotation, lead time and CE and IP20 certification documents. OEM/ODM and private label orders are supported with grey or white fascia options, branded packaging, pre-configured weekly schedules and drop-ship logistics. MOQ and pricing depend on model and quantity.

Start your order by contacting our sales team with the load type and quantity, or message us on WhatsApp for the fastest reply. Browse the full range on the thermostats and controls category page, compare the SDM6 with our linear LED WiFi thermostat, the black-glass touch WiFi thermostat and the piano-key WiFi heating thermostat, and see typical installs on the applications page. More questions are collected on the FAQ page.

FAQ (continued)

9. Can I buy the SDM6 wholesale or as a private-labelled product?

Yes. SunAura offers wholesale price breaks, EXW or FOB quotations, CE and IP20 certification documents and private-labelling on the fascia and packaging for distributors and OEM partners. Choose the grey or white front panel and the 16 A electric or 3 A dry-contact version, and we will quote MOQ, lead time and sample options the same day.

10. What is the difference between NO and NC on the 3 A version?

The 3 A version gives you both a normally-open (NO) and a normally-closed (NC) dry-contact loop, so the SDM6 can match the call-for-heating logic of most wall-hung boilers and thermal actuator valves. Wire only the pair your boiler or actuator requires and leave the other pair unused — confirm the terminal labels on the backplate before powering up.

11. How is the ring display easier to read than a plain digital number?

The large outer ring shows measured ROOM TEMP and the smaller inner readout shows the SET target, so the gap between them is visible from across a room — useful in hallways, hotel lobbies and offices where people glance at the thermostat without walking up to it. The clock, week, weather and child-lock icons sit around the dial for extra context.

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