FCU and AHU brands that still ship three-speed coils do not need a retail wall brick. An OEM Modbus relay thermostat puts 230 VAC relays, a Modbus citizen, and your glass on the same flush square — without assuming an EC fan path or an installer webshop SKU.
OEMModbusRelayFCUHVAC230 VAC
Alledio’s OEM Thermostat is that class of device. It is designed in Slovenia and manufactured in the EU. Relays switch the coil and the three-speed fan. The glass, the sensors, and the bus are the brand face the occupant sees.
Who this is for
This article is for OEM product managers, FCU and AHU brand owners, and BMS device makers who need a branded relay thermostat at production volume, not a one-off installer SKU.
Typical applications on the product page are fan coil units, air handling units, DX equipment, and other local HVAC systems that need relay outputs. Installers and system integrators cannot buy Alledio direct. The commercial model is high-MOQ OEM. The usual MOQ is 1,000 pcs, and it is negotiable.
This is not the Room Unit. That SKU is a low-voltage, host-driven wall UI. This post is the Alledio OEM Thermostat — 230 VAC, fan-speed relays, heat/cool relays. If you need more standalone I/O in the same family, that is the Room Controller, not this SKU.
Bring the FCU or AHU controls engineer into the same call as industrial design. One team owns the glass. The other owns the contact schedule. When those two briefs are written as one RFQ, NRE stays on logo and UI instead of a second electronics spin. That is the practical meaning of an OEM programme.
Write the documents you want back: ICD, register list, mechanical drawing, and a short integration note for the coil team. Name who approves artwork and who signs the Modbus map. Commissioning should not invent a field dialect on site.
When to specify an OEM Modbus relay thermostat
Write the RFQ around relays first. Speed 1, 2, 3, Auto, and off are contact closures. Heat and cool are contact closures. Do not paste a 0–10 V fan line into this RFQ unless you quoted a different model.
Relays first, then the bus map
Modbus RTU on RS-485 is the supervisory copper pair. Baud, parity, address, and the register map belong in the same pack as the logo. Wi-Fi 2.4 GHz STA is listed for connected SKUs; MQTT is named for cloud or proprietary web services. That radio does not replace the copper pair.
Failsafe and offline behaviour to write in the RFQ
Failsafe language belongs in the RFQ: what the relays do on bus loss, what the glass shows when the host is offline, and whether anti-freeze or a temporary fan boost is firmware NRE. Those are programme decisions, not catalogue surprises. Andivi will be at MCE Milano 2026 if you want that conversation in person.
What branding changes on a relay thermostat SKU
Buyers lose months when “white label” means a sticker on a catalogue thermostat. A useful RFQ lists each surface, who owns the artwork, and whether the change is NRE or a catalogue option.
OEM customisation is the NRE path: exterior logo, UI colours, widgets, housing colourways (white, black, silver, plus custom), optional VOC and CO2, packing and docs. You pay for the delta, not for a new radio and a new mould. A hotel pack and an office pack can share one electronics revision.
The same brand surfaces a white label HVAC room display RFQ should list still apply here — but the platform under them is the relay thermostat, not the low-voltage Room Unit.
State MOQ, sample count, NRE for firmware, and who owns the register map before you ask for a colourway. Ask for the cable class you already pull for RS-485 and the slave-ID plan. Bring artwork early: logo on glass, UI chrome, and the exact colour codes for housing. That pack is what turns a pretty glass into a line item.
How the room feels, not only how the glass looks, is also the thread of Beyond design: it’s how it feels. A white-label thermostat still has to sit quietly in a hotel corridor and read clearly in an office lobby. Write brightness, night schedule, and absence behaviour as firmware requirements, not as afterthoughts.
Relays, I/O models, and what not to invent
Power on the thermostat page is 230 VAC. Mechanics you can defend today: 98 × 98 × 14 mm, 150 g, IP20, ABS plus scratch-resistant glass, flush-mounted in a standard EU box (Ø 60 mm). Display is 3.5" LCD at 480 × 320 with capacitive touch and a brightness sensor.
Four thermostat models are listed for I/O flexibility: 2 × AO, 2 × DO, 1 × AO plus 1 × DO, and 2 × relay heat/cool, on top of power, Modbus, and the fan-speed relays. Those analogue and digital options are models. They are not a licence to write EC fan control into the RFQ.
Not a catalogue SKU here: KNX. Other buses are OEM firmware or hardware work, quoted separately. Do not write a Nest-style retail part number into this RFQ.
Bluetooth 5 LE is ready on the platform; the GATT map is a client specification. OTA firmware updates are listed. Use Wi-Fi when the SKU needs OTA or a named cloud path. Use RS-485 when the BMS is already on a bus. Write that split so field teams do not stand up an unquoted radio.
Recuperation views, sanitary warm-water shortcuts, temporary fan boost, and similar application widgets are described as firmware that can sit on the same design library. Quote those as firmware NRE. Do not hide them inside a sentence that sounds like EC control.
Name the sample count you need under NDA and whether demo firmware or test firmware is required for the first bench. Write who owns the artwork and who owns the register map. Those two owners should sign the same RFQ so NRE does not split into two silent projects. That is how OEM programmes stay honest on MOQ.
Thermostat vs Room Unit vs Room Controller
If several brand versions share electronics and only differ in logo and colour, say so in the RFQ. Combined quantity over 1,000 pcs may open a path down to 500 on a version — confirm that rule for this thermostat SKU on the OEM page; do not assume Room Unit or Room Controller quantity logic applies automatically.
Do not promise an installer webshop, a Nest-style retail box, or a catalogue KNX SKU in the same sentence as this thermostat. Those promises break channel strategy and force a redesign. Alledio sells to OEMs. Your channel sells to installers. Keep that split as a commercial rule.
Product proof
| Topic | Published spec |
|---|---|
| Product | Alledio OEM Thermostat (Modbus / relay) |
| Power | 230 VAC |
| Fan relays | Speed 1 / 2 / 3 / Auto / off |
| H/C relays | Heating / cooling |
| Display | 3.5" LCD, 480 × 320, capacitive touch, auto brightness |
| Sensors (standard) | Digital temperature and humidity |
| Sensors (optional) | VOC, CO2, external NTC |
| Bus | RS-485 Modbus RTU, half-duplex |
| Wi-Fi | 2.4 GHz (802.11 b/g/n) STA |
| Mechanics | 98 × 98 × 14 mm, 150 g, IP20, EU flush box Ø 60 mm |
| Origin | Designed Slovenia, manufactured EU |
| Standards | CE, EN 60730-1, EN 60730-2-9, EN 300 328 V2.2.2 |
| Security support | 5-year update window |
Use this table in the brand pack, then attach your logo and UI screens separately. Current and power-consumption cells are unpublished on the product page; leave them empty until the datasheet is current.
FAQ
Can an installer buy this from a webshop?
No. Alledio sells to OEMs. Installers and SIs get devices through your channel.
Does this put the plant in the wall?
No. Relays switch fan and heat/cool. Sequences and safeties that belong on your FCU or AHU controller stay there unless you quoted the Room Controller.
Should we assume EC or 0–10 V fan control?
No. The published fan path is relays. Ask analogue fan as a separate question.
Can we get samples?
Yes. Samples are available with demo firmware or test firmware, under NDA. This is not a webshop SKU. Start on /oem.
What is the MOQ?
The usual MOQ is 1,000 pcs, and it is negotiable. If you order several thermostat versions that share electronics and only differ in logo or colour, and the combined quantity is over 1,000 pcs, ask on /oem whether a path down to 500 on a version is available for this SKU.
Is this a Nest-style retail thermostat?
No. It is a white-label OEM thermostat for HVAC brands.
What to do next
Start on the Alledio OEM Thermostat page, then open an OEM conversation for logo, UI, firmware and samples. Bring fan type (three-speed relays, not assumed EC), 230 VAC, Modbus map, MOQ, and the artwork for the glass. That is how an OEM Modbus relay thermostat becomes a branded SKU instead of a sticker.
