KNX Fan Coil Controller Supplier | HT-FCU Series (3-Speed & 0-10V)

The HT-FCU range

One family, five controller models and two matched room thermostats — pick by pipe system, fan type and protocol

Model	Fan output	Pipe system	Valve / relay outputs	Protocol	Typical use
HT-FCU-3S2	3-speed, 230 V AC	2-pipe	2 (heating / cooling, seasonal changeover)	KNX TP1	Standard guest room, 2-pipe fan coil
HT-FCU-3S4	3-speed, 230 V AC	4-pipe	4 (2 heating + 2 cooling)	KNX TP1	4-pipe suites, separate heating and cooling loops
HT-FCU-0102	0-10 V, EC / brushless	2-pipe	2 (0-10 V modulating or thermal)	KNX TP1	Quiet rooms, EC motor retrofit, low-speed night operation
HT-FCU-3S2-MB	3-speed, 230 V AC	2-pipe	2	Modbus RS-485	Mid-tier projects on a cost target, BMS via Modbus
HT-FCU-3S4-MB	3-speed, 230 V AC	4-pipe	4	Modbus RS-485	4-pipe buildings with an existing Modbus backbone
HT-FCU-3S2-BL	3-speed, 230 V AC	2-pipe	2	Bluetooth Mesh	Occupied-hotel renovation, no control wiring available
HT-FCU-TS01	— (room thermostat)	Paired with the above	—	KNX TP1	In-room setpoint, fan speed and mode selection
HT-FCU-TS02-MB	— (room thermostat)	Paired with the above	—	Modbus RS-485	Modbus rooms needing a local setpoint panel

All controller models share the same DIN-rail footprint and terminal layout, so a project can start on Modbus and move to KNX without re-drilling the distribution board. Model codes are our commercial ordering codes; the KNX-certified article number is confirmed in writing on the quotation for the exact model you specify.

Which model fits your project

Five questions decide it — the rest is detail

How many pipes?

Two pipes carry either chilled or hot water and switch over by season — that is HT-FCU-3S2. Four pipes carry both at once with independent valves — that is HT-FCU-3S4.

Which motor?

An ordinary AC fan has three tap speeds and is switched by relays. An EC or brushless motor takes a 0-10 V signal and runs far quieter at low speed — that is HT-FCU-0102.

Which bus?

KNX where the consultant specified an open standard and ETS6 commissioning. Modbus RS-485 where the BMS is already Modbus and the budget is tighter. Bluetooth Mesh where no control cable exists.

Thermostat or not?

HT-FCU-TS01 adds the in-room panel for setpoint, fan speed and mode. Projects that use a KNX touch panel instead can drive the controller straight from the panel and skip the thermostat.

New build or renovation?

New build: DIN-rail controller in the room distribution board. Renovation with ceilings already closed: the BLE Mesh model removes the control cable run entirely.

Technical advantages

The controller is the actuator layer of the room: it owns the fan taps, the valves and the setpoint, and it reports back. That is what makes a GRMS able to save energy without touching the guest experience.

Fan coil control for 2-pipe and 4-pipe units from one family
Three fan speeds plus PI-controlled valves, or 0-10 V modulating output
Seasonal changeover by digital input (NTC10K / PT1000 water sensor)
Window contact, card holder and condensation switch inputs on board
Setpoint limits enforced in the device, not only in the head end
Occupancy setback triggered by KNX object, card holder or PMS event
Local frost protection that keeps working if the bus goes down
ETS6 application program with a documented group-object list

Common specifications

Bus / logic supply21–30 V DC from KNX bus, ≤12 mA

Auxiliary supply230 V AC 50/60 Hz (fan and valve loads)

Fan outputs3 speeds, 6 A each at 230 V AC

Valve outputsUp to 4; 230 V AC thermal or 0-10 V modulating

Digital inputs4 (window, card holder, condensation, changeover)

Max total load10 A per device

Mounting35 mm DIN rail, 72 x 90 x 63 mm

ProgrammingETS6 (KNX) / register map (Modbus) / Hotekey app (BLE)

Operating range-20 °C ~ +50 °C, 1–100% RH non-condensing

Ingress protectionIP20 (inside the room distribution board)

Load figures are per model. Send the fan coil schedule (unit model, motor type, valve type, pipe count) and we return the matching HT-FCU code with a wiring diagram — that is faster and safer than picking from a table.

Where the fan coil controller sits in a hotel GRMS

Three layers, three owners — the controller is the one that actually moves the valve

PMS — front desk

Reservations, billing, check-in and check-out. It knows a room is sold. It does not know the room is 26 °C.

GRMS — room layer

Room status, scenes, DND / MUR, energy logic. It decides that a sold-but-empty room should sit at a setback setpoint.

FCU controller — actuator layer

Takes that decision and drives the fan tap and the valve. This is the HT-FCU. It also enforces setpoint limits and frost protection locally.

Because the controller is hardware, not software, a hotel can change PMS or GRMS vendor without touching the room. That is the main reason owners separate the two decisions. The room-level logic is described in more detail on the KNX hotel GRMS page and the GRCS vs GRMS page.

Commissioning and handover

What the integrator actually receives, so the first room is not the learning curve

Step	What happens	What is handed over
1. Selection	Fan coil schedule reviewed, model code and valve type matched per room type	Model list per room type, wiring diagram
2. ETS6 setup	Application program loaded, group addresses mapped to the room template	.knxproj with the room template, group-object list
3. First room	Fan taps, valve direction, changeover, window and card-holder logic verified on site	Commissioning record with measured values
4. Rollout	Template copied per floor; only room address and setpoint limits change	Floor-by-floor test sheet
5. After-sales	Spare controllers held for the warranty period, remote support for odd faults	Named contact, spare-parts policy

Two details cause most call-backs and both are settled at commissioning, not in the factory: valve stroke direction (normally closed vs normally open) and the changeover sensor curve. Write both into the handover record.

Questions buyers ask before specifying

The ones that decide the model, answered the way we answer them on a call

What is the difference between a KNX fan coil controller and a KNX thermostat?

The controller is the actuator: it switches the fan taps and drives the valves, and it lives in the room distribution board on DIN rail. The thermostat is the sensor and user interface on the wall. Some projects put both functions in one wall device; the HT-FCU range keeps them separate so the controller can sit next to the fan coil and the panel can be chosen for design.

Can one controller run a 4-pipe system with seasonal changeover?

A 4-pipe system needs HT-FCU-3S4, which has independent heating and cooling valve outputs. A 2-pipe system with a single coil uses HT-FCU-3S2 plus a water temperature sensor on the changeover input, so the controller knows whether the loop is carrying hot or chilled water and locks out the wrong mode.

Do you have a 0-10 V version for EC motors?

Yes, HT-FCU-0102. It drives an EC or brushless fan with a 0-10 V signal and controls the valves either by 0-10 V modulation or by thermal actuators. EC motors are the reason to specify it: below 40% speed they are close to inaudible, which matters in rooms where the fan runs all night.

Which valve actuators can the controller drive?

230 V AC thermal actuators (on/off), 0-10 V modulating actuators, and 3-point motorised valves on the models that expose them. The total load per device is 10 A, so a room with two large thermal actuators plus three fan taps stays well inside the limit.

Does it need a separate 230 V supply?

Yes. The KNX bus powers the logic only. The fan taps and the valves are mains loads, so each controller needs a 230 V AC feed in the room distribution board. That is normal for DIN-rail KNX actuators and it is why the controller sits next to the MCBs rather than behind the wall panel.

Can the HT-FCU be supplied with our brand and our firmware settings?

Yes. Model code label, packaging, terminal marking, default setpoint limits, fan-speed policy and the room template in the ETS6 project can all carry your brand and your commissioning method. That is the OEM route described on the OEM & ODM page.

KNX Fan Coil Controller — HT-FCU Series