Hotel fan coil projects are won or lost on the wall. Guests judge the room by one small screen, operators judge it by the energy bill, and the integrator judges it by the point list. This guide turns those three views into a requirements checklist for an FCU hotel room OEM thermostat, written for HVAC OEM product managers and R&D engineers who ship fan coil units into hotels. It covers guest comfort, occupancy logic, Modbus integration, branding and commercial terms, using the published Alledio Thermostat as the reference device.
White LabelFCUOEMHVACHotelTemperature
Why a hotel changes the FCU hotel room OEM thermostat brief
An office fan coil serves the same people every day, and they learn the controls. A hotel room serves a new guest every night, often tired, often jet-lagged, and never trained. The wall device has to explain itself in seconds and still look right beside premium joinery.
The operator adds a second set of demands. Rooms sit empty for long periods, windows open, keycards are pulled, and the building management system expects every room to report the same points in the same way. The thermostat becomes a networked room node, not just a setpoint dial.
For the OEM, the result is a tighter specification than a standard fan coil package. Hotel chains also repeat projects across many sites, so a well-defined hotel SKU can carry volume for years once it passes the first fit-out.
Guest-room requirements to put in the RFQ
Comfort the guest can understand
Start with the user journey. A guest should see the room temperature, change the setpoint, and pick a fan speed without a manual. Keep the main screen to three or four controls and hide installer menus behind a service PIN.
Write setpoint limits into the requirement, for example 19 to 26 °C for guests, with a wider band reserved for maintenance staff. Limits protect the plant, and they prevent the open-window, full-cooling pattern that drives hotel energy costs.
Quiet nights and a dark room
Fan noise is the most common complaint in fan coil rooms. On a three-speed motor, auto mode should prefer speed 1 at night and step up only when the temperature error grows. Ask for a night fan limit as a parameter the operator can set per property.
Light matters as much as sound. The Alledio Thermostat has an ambient brightness sensor, so the screen can dim in a dark room. Specify the night brightness level and the wake behaviour on touch, because a glowing panel next to the bed generates complaints too.
Occupancy, keycard and window logic
Most hotels set back the room when the keycard is removed or the window opens. Decide early where that signal enters: a keycard switch wired to the BMS or a room controller, or a dry contact at the thermostat itself.
The published Thermostat I/O models list one NTC input plus outputs, and do not list a dedicated keycard input. The clean pattern is to pass occupancy over Modbus from the room host or BMS; if a local contact is mandatory, raise it in the RFQ as OEM hardware scope.
What an OEM Modbus relay thermostat must deliver in a guest room
Most hotel fan coils still run tapped three-speed AC motors on a 2-pipe or 4-pipe water system. That makes a 230 VAC relay device the natural wall node. The table maps each requirement to what the Alledio Thermostat publishes today and to what your RFQ should state.
| Requirement | Published on the Alledio Thermostat | What to write in the RFQ |
|---|---|---|
| Supply | 230 VAC on the wall, flush in a standard EU Ø60 mm box | Confirm mains is allowed at the wall in every target market |
| Fan | Relays for three fan speeds: 1 / 2 / 3 / auto / off | Name the motor type and the maximum relay load per tap |
| Heating and cooling | Four I/O models: 2 × 0-10 V, 2 × digital output, 1 + 1 mixed, or 2 × relay H/C | State 2-pipe or 4-pipe and the valve type per room type |
| Sensors | Temperature and humidity; VOC and CO2 optional; NTC input on every model | List which rooms need IAQ and where a remote probe sits |
| Bus | RS-485 Modbus RTU, client or server, address 1-247, ¼ unit load | Attach the BMS point list and the trunk length per floor |
| Guest UI | 3.5 inch 480 × 320 capacitive glass with ambient brightness sensor | Define setpoint limits, guest lockouts and night dimming |
| Brand | White, black or silver; logo and UI theme per OEM | Supply the hotel brand assets and any per-chain variants |
| Lifecycle | OTA updates over Wi-Fi; 5 years of security updates | Ask for the update and support policy in writing |
The Thermostat switches fan speeds on its own relays and talks RS-485 Modbus RTU at baud rates up to 115200. For the relay and bus fundamentals, read the OEM Modbus relay thermostat guide; for the motor decision behind it, see the EC fan vs 3-speed AC fan coil comparison. Keep the published scope separate from anything you want added.
Wi-Fi on the Thermostat is 2.4 GHz and is used today for firmware updates; MQTT and an API are available for OEM integration, and BLE 5 is hardware-ready. Do not promise guest phone control in a hotel tender unless it is quoted as OEM firmware work.
Wiring and I/O behind the hotel wall
Hotel walls are shallow and full of services. The Thermostat measures 98 × 98 × 14 mm and mounts flush in a standard EU Ø60 mm box, so it fits the back boxes electricians already install for switches and sockets.
On the 2 × relay H/C model shown above, the upper terminal block takes L, N, the NTC probe and Modbus A, B and GND. The lower block carries the heating and cooling relays and the three fan relays R1, R2 and R3 with their common. Analogue and digital output models replace the H/C pair to suit modulating or thermal valves.
Plan the RS-485 trunk per floor, not per room. At ¼ unit load the Thermostat allows up to 128 devices on one segment, which covers most corridors with spare capacity. Use twisted pair with a shield, terminate both ends, and keep the trunk away from mains runs where the riser allows it.
When the fan relays must sit inside the unit rather than behind the wall, the Modbus relay extender pattern keeps mains switching out of the guest room wall entirely.
BMS and Modbus points a hotel operator expects
Hotel integrators want a repeatable point list, not a different map for every room type. Agree the register map once and freeze it for the whole programme, so commissioning becomes copy and verify.
- Room temperature, humidity and, where fitted, VOC or CO2.
- Active setpoint, guest offset and the operator setpoint limits.
- Fan command and fan status: off, 1, 2, 3 or auto.
- Heating and cooling demand or valve command.
- Occupancy and window state written by the BMS, plus a setback mode.
- Alarms such as probe failure, anti-freeze and communication loss.
Define what the room does when the bus goes silent. A sensible default keeps the last setpoint within limits and falls back to anti-freeze protection in empty rooms. Before site, test the map on the bench with a free browser tool such as Modbus Mate, then check slave addresses floor by floor against the protocol rules published at modbus.org.
If the project needs low-voltage universal I/O, keycard inputs on the wall node and a 0-10 V EC fan, the better fit is a controller rather than a thermostat. The hotel fan coil room controller with Modbus covers that low-voltage path, built on the Alledio OEM Room Controller.
Branding, variants and commercial terms for hotel programmes
Hotel chains care about how the room looks. The Thermostat ships in white, black and silver with ABS and glass, and the OEM version carries your logo and UI theme. Many OEMs keep one hardware platform and switch colour per brand standard or room category.
Write variants into the RFQ as a short matrix: colour, I/O model, IAQ option and firmware profile. That keeps purchasing, production and the hotel designer aligned. The white label FCU thermostat article shows how a branded SKU is defined end to end.
Compliance is part of the hotel file. The Thermostat lists CE marking with EN 60730-1, EN 60730-2-9 and EN 300 328, IP20 and an operating range of −10 to +50 °C. Keep these on the submittal sheet and do not add certifications the datasheet does not show.
Commercially, Alledio works OEM-only. MOQ is 1,000 pcs and negotiable, firmware changes are quoted as NRE, and samples come with demo or test firmware. For the three-speed selection criteria behind a hotel SKU, the 3-speed FCU OEM thermostat buyer guide lists the RFQ fields purchasing will ask for.
FAQ
Can a hotel or installer buy one thermostat directly?
No. Alledio sells OEM-only to companies that build fan coil units or other HVAC equipment. Hotels get the device through the OEM that supplies their units.
Does the thermostat run the whole room plant?
It runs the fan coil: three fan speeds, heating and cooling outputs and the local sensors. Plant-wide logic such as chillers, boilers and central scheduling stays in the BMS.
How does keycard occupancy reach the thermostat?
The recommended pattern is a Modbus write from the room host or BMS. A dedicated keycard contact on the wall device is not a published input, so request it as OEM scope if you need it.
Is there a KNX version?
No. The published Thermostat uses RS-485 Modbus RTU. Gateways are a project decision, not a separate Alledio SKU.
Can we get samples before the hotel fit-out?
Yes. Samples are purchased and ship with demo or test firmware, so your team can mock up a guest room and test the sequence first.
What is the MOQ?
MOQ is 1,000 pcs and negotiable. Custom firmware and branding work are quoted separately.
What to do next
Turn the checklist above into your FCU hotel room OEM thermostat RFQ, then compare it against the Alledio OEM Thermostat page. Start an OEM conversation to request samples with demo firmware and a quote for your hotel fan coil range.
