SDM5 WiFi Smart Thermostat with LED Display

Overview

The SunAura SDM5 is a wall-mounted WiFi smart thermostat with a green-backlit LED digital display, engineered to control three families of heating system from one slim 86×86 mm plate: electric heating such as underfloor heating mats, heating cables and infrared wall panels; water heating systems such as hydronic underfloor loops and radiator zones; and wall-hung gas boilers. Instead of a glass touch surface, the SDM5 uses three physical side buttons — M, up and down — so the set temperature can be adjusted by feel, even with cold hands or without taking your eyes off the room.

Where the SDM5 differs from a basic LED thermostat is the control layer behind the screen. The display follows a clean linear layout — room temperature on the left, the SET target in the centre, and the clock on the right — while a WiFi connection adds full smart-home operation: the thermostat pairs with a Tuya-compatible app for remote temperature control, weekly programming, child lock and power-off memory, and it works with Amazon Alexa and Google Assistant for hands-free voice control. White and grey front panels are offered so the unit can be matched to different wall decors and interior styles.

The SDM5 is manufactured by SunAura Thermal, an ISO-managed factory in Qingdao, China, with more than 17 years of OEM/ODM experience supplying heating controls to 50+ countries. Every unit is tested before shipment and carries CE compliance and IP20 ingress protection, with factory quality documentation available on request.

Key Features

• Green-backlit LED digital display — a clear segmented LED screen with soft green backlight showing room temperature, set temperature and clock in a linear arrangement, readable day and night without glare.
• Physical side buttons M / ▲ / ▼ — three tactile keys on the side edge for mode, up and down; no fragile touch glass, no accidental wipes, easy to operate by feel.
• One thermostat, three heating types — the same platform covers electric heating (16 A resistive), water heating (3 A resistive) and wall-hung boilers, so installers standardise on one product line.
• Weekly programming, 6+2 periods — six independent time-and-temperature periods for weekdays and two relaxed periods for weekends, programmed comfortably in the app.
• App remote control — full operation through a Tuya-compatible app on iOS and Android: set temperature, switch mode, edit schedule and monitor the room from anywhere.
• Voice control — works with Amazon Alexa and Google Assistant, so you can ask for the current temperature or adjust the setpoint hands-free.
• Child lock — a lock icon appears on the LED screen and the keys are disabled until you unlock, keeping settings safe from curious hands.
• Power-off memory — all user settings are retained when power is cut; the SDM5 resumes the last programme automatically, with no re-programming after an outage.
• Flame-retardant housing — the front casing is moulded from flame-retardant material, demonstrated in our burn test, for an extra margin of safety behind the wall plate.
• External probe terminal — a dedicated external sensor connection allows floor or pipe temperature measurement in demanding heating installs.

Display & Icon Guide

The SDM5 screen communicates the full heating state at a glance, in a strict linear layout. On the left, the room temperature reading shows the current measured space temperature; in the centre, the SET label marks the target temperature so it is never confused with the measured value; on the right, the clock shows the current time. Above these numbers, the week display indicates the current day, the weather icon reflects outdoor conditions pulled from the linked app, the heating icon lights when the output relay is energised, and the child-lock icon confirms that the side buttons are locked.

Physically the SDM5 measures 86 × 86 × 14 mm, matching the standard 86 mm wall-box mounting grid used across Europe and Asia, and its slim depth keeps it flush against the wall in living rooms, bedrooms, bathrooms, offices and hotel rooms.

The weekly programme follows a 6+2 structure: six independently timed periods for weekdays and two relaxed periods for weekends, each with its own target temperature. Three schedule templates are available in the app — 5+2, 6+1 and 7-day — so the programme can follow a standard work week, a six-day working week, or a fully individual seven-day routine. Every period can be renamed and re-timed directly in the app, and the schedule then runs automatically on the wall unit, even without a phone nearby.

Technical Specifications

Applications

The SDM5 covers the three most common residential and light-commercial heating control jobs from a single 86 mm plate:

• Electric heating — underfloor heating mats, heating cables, infrared wall panels, towel rails and similar resistive loads up to the 16 A rating.
• Water heating / hydronic underfloor — 3 A resistive switching for zone valves and pump-driven hydronic loops, where a full-power relay would be overkill and wasteful.
• Wall-hung boilers — ON/OFF room thermostat control for gas boilers, replacing the boiler’s basic built-in thermostat with a programmable, app-connected unit.

Because the same enclosure, display and app experience serve all three load types, distributors can stock one SKU family, electric and water variants side by side, and installers only ever learn one menu logic.

Installation

1. Isolate the supply — switch off the circuit at the consumer box before opening the wall box.
2. Wire the backplate — connect mains live and neutral to L and N, the switched output to L1 / N1, and the external floor or pipe probe to the probe terminals. Confirm you are using the 16 A electric version for electric heating loads or the 3 A water / boiler version for hydronic and boiler circuits, and never exceed the rated output.
3. Clip on the front panel — seat the LED front panel onto the wired backplate until it clicks; the panel removes without tools for servicing.
4. Power on and pair — restore power, hold the pairing key sequence, and add the unit in the Tuya-compatible app over a 2.4 GHz WiFi network; set your weekly schedule in the app.

All wiring must be carried out by a qualified electrician, and the connected load must not exceed the rated output of the chosen version. A dedicated installation guide and wiring diagram ship with every order, and our engineers are available by WhatsApp for remote commissioning support.

Compatibility with SunAura Heating Systems

The SDM5 is the natural control partner for the full SunAura heating range. On the electric side it pairs with SunAura heating films, heating mats and heating cables; on the wet side it pairs with hydronic underfloor zones and wall-hung boiler installations. When you order a complete heating system from SunAura, we can pre-configure the SDM5’s set range, schedule template and sensor selection — internal air sensor or external floor probe — to match your exact installation, and ship the whole package: heater, thermostat, sensors and accessories, from a single factory source with one warranty and one after-sales contact.

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 SDM5 is CE compliant and IP20 rated, and its flame-retardant housing material is tested as part of the incoming-material control process. We support distributors and OEM customers with private-labelled branding, custom schedule templates, packaging design and drop-ship logistics to more than 50 countries.

FAQ

1. How do I adjust the temperature with the side buttons?

Press the ▲ or ▼ side button to raise or lower the set temperature; the SET value on the LED screen changes as you press. Press the M button to switch between modes such as manual, programmed and child-lock control. The linear screen layout means the room temperature, set temperature and clock are always visible at the same time.

2. What is the difference between the 16 A and 3 A versions?

The 16 A resistive version is intended for electric heating — underfloor mats, heating cables and infrared panels directly switched by the thermostat. The 3 A resistive version is intended for water heating and wall-hung boilers, where the load is a zone valve, pump or boiler ON/OFF demand rather than a direct heating element. Please confirm the load type when ordering so we ship the correct variant.

3. How do I pair the SDM5 with the app?

Download the Tuya-compatible app, create an account, add a new device and select the thermostat category. Put the SDM5 into pairing mode with the side-button key sequence, confirm the WiFi network name and password (2.4 GHz only), and the unit appears in the app within a minute. From there you can set the weekly schedule remotely and enable voice control.

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

All settings — schedule, set temperature, mode and child-lock state — are stored permanently in the device memory. When power returns, the SDM5 resumes the last programme automatically, with no re-programming needed. The standby consumption remains below 1 W, so the unit is economical even on standby.

5. Can I use an external temperature sensor with the SDM5?

Yes. The backplate provides a dedicated external probe terminal alongside the L / N / N1 / L1 mains terminals. Connect an NTC floor or pipe probe when you need to measure a surface or fluid temperature rather than the air near the wall, and select the sensor source in the device settings. Sensor accuracy is ±1 °C.

6. How does the weekly programming work?

The SDM5 runs a 6+2 programme: six independently timed periods for weekdays and two relaxed periods for weekends, each with its own target temperature. In the app you can switch between 5+2, 6+1 and 7-day templates, rename each period and adjust its times and temperatures. Once configured, the schedule runs automatically on the wall unit even when the phone is not nearby.

7. Is the SDM5 safe — what does the flame-retardant housing mean?

The front casing is moulded from flame-retardant material; we demonstrate this with a controlled fire-bubble test of the finished unit. Combined with the child lock and the rated-output wiring limits, this gives an extra margin of safety in living rooms, bedrooms and hotel rooms. The unit is also IP20 protected against solid objects and standard household dust.

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

Every SDM5 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. Distributor and OEM customers also get private-labelling, custom schedules and packaging support from our Qingdao factory.

Looking for a green backlit LED WiFi thermostat with side buttons that is easier to operate by feel than a flat touch panel? The SunAura SDM5 is an affordable 16 A WiFi thermostat for electric underfloor heating that also covers water heating and wall-hung boilers from the same 86 mm plate, with a WiFi boiler thermostat with 6+2 weekly schedule programmed comfortably in the app. The factory notes below cover ordering, version selection and the questions installers ask most often before placing a carton order.

How to Buy from SunAura Factory

SunAura Thermal supplies the SDM5 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 or the 3 A water/boiler version, 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 white or grey 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 heating 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 SDM5 with our black-glass touch WiFi thermostat, the ring-display WiFi smart thermostat and the basic non-programmable room thermostat, and see typical installs on the applications page. More questions are collected on the FAQ page.

FAQ (continued)

9. Can I buy the SDM5 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 white or grey front panel and the 16 A electric or 3 A water/boiler version, and we will quote MOQ, lead time and sample options the same day.

10. Why choose side buttons instead of a touch screen?

The three physical side keys (M, ▲, ▼) are easier to operate with cold, wet or gloved hands, and they do not change settings when a sleeve or duster brushes across the face. That makes the SDM5 a practical choice for bedrooms, hotel rooms and office corridors where a glass touch panel can be fiddly.

11. Can one SDM5 control both electric underfloor heating and a wall-hung boiler?

One SDM5 covers one heating zone, so use the 16 A version for electric underfloor mats, cables or panels, and the 3 A version for water heating manifolds or a wall-hung boiler call-for-heating loop. For mixed homes, install one SDM5 per zone — they can all share the same app account and the same 6+2 weekly schedule logic.

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