The TTC supply air diffuser controls the ventilation with the help of the built-in sensor for occupancy, temperature and flow (also pressure). When the room is empty, the system goes into economy mode, returning to comfort mode when the occupancy detector is triggered (after an adjustable time delay). The flow is then raised to an "occupancy flow" (typically 10-12 l/s); when there is excess heat the air flow increases to achieve the right temperature. For maximum energy saving, strongly under-temperature air is used to reduce the fan electricity consumption as the flow becomes lower.


The design of the diffuser means that the diffuser can reduce very high pressures without noise problems, which means that it is suitable for renovation projects where existing ducts can be exploited without risk of excessively high noise levels.


The diffuser can control heating in sequence with radiator actuators and also functions with thermostats, but it can then be more difficult to exploit economy mode when the office is not occupied; there can also be a risk that heating and cooling will operate simultaneously. However, this scenario can be easily detected with our web server LINDINSPECT.

TTC can also work with over-temperature air with good mixing, but if the supply air temperature cannot be adapted for different parts of the property, this tends to be a rather "insensitive" solution.


The CBR relay box makes lighting control easy and cheap. If you use a switch for active switching on and allow the occupancy detector to control switching off, research has shown that the glass part of the façade must exceed 40% for daylight compensation to be worthwhile.


As the supply air diffuser has all of the sensors built in to the diffuser and does not require any installation on the walls, extremely high flexibility and simple management are obtained when walls are to be moved or removed. The fact that the sensors are not wall-mounted also gives a quicker time constant on the temperature sensor, and tampering is avoided.

Standby kill switch

Standby use constitutes approx. 50-100 kWh/m2 per year. Controlling this with a timer and cutting the power between 23:30 and 06:00 means that a large share of the savings is lost. With our wireless controller units WTR and WRS, electrical outlets can be controlled with the occupancy sensor in the diffuser and then maximum savings can be made.

Cellular office with supply air via the TTC active supply air diffuser that uses a built-in regulator and sensor to regulate temperature and air quantity in the room by increasing or decreasing the slot size between the blades in the diffuser section. Pressure and flow sensors and encoders on the motor ensure extremely accurate flow regulation and make possible pressure optimization of the aggregate. The flow is set at three different levels: absence, occupancy and maximum flow. The built-in occupancy detector also controls economy and comfort modes after an adjustable time delay.

Extract air

Extract air via transmitted air to corridors with flow balance regulation through the flow that is communicated by digital bus. Adjustable offsets compensate for fast flows such as WC groups etc.


Via the CBX connection box, the supply air diffuser regulates the A4004 valve actuator on the radiator. Adjustable cold draught protection. The flow temperature and circulation pump on/off for heating can be optimized.

Extra heating/cooling steps

Further heating or cooling steps can be connected in the CBX box for extreme operating cases.

Extra sensors

CO2 or air quality sensors can be connected in the CBX box. This input can also be used for other sensors if required. The sensor signal is used to regulate an adjustable P band.


The CBR lighting control box is used to connect push buttons and 230 VAC to the lighting system. The lighting is turned on and off either via a signal from the occupancy sensor placed in the supply air diffuser or from connected push buttons. The time to automatic switch-on (one operating mode) can be set, as can the time to switch-off after the last recorded movement. The number of on and off operations and the number of hours with lighting illuminated are registered for measurement of the number of burning hours for the armature and thereby the optimal time for replacing fluorescent tubes.

The cable used throughout is a PVC-free shielded combined supply and communication cable. It is pre-terminated in the diffuser's diffuser section with ready-made contacts in the other end for rapid installation. For other products, it is connected in the same way throughout.

Cable lengths

The bus cable can be pulled for long distances in respect of communication, but the voltage drop must be taken into account for power supply. See electricity design guide.

The limiting factor for cable length is that each CMA ("communication hub") can only have 100 nodes/products installed on it.

Power supply and transformers

In a normal situation, one transformer is installed per 12-15 diffusers/products but this is a rule of thumb that applies with short distances between products. See electricity design guide.

In some cases, you may wish to place a larger transformer in cable recesses instead of many smaller ones deployed throughout the installation. This can be done, but you must take note of the voltage drop in cables, and you will need separate thick 24 VAC cables on cable ladders...

Different installation principles for easiest/cheapest installation

Instead of pulling the cable on a ladder outside the cellular office, you can pull the cable in line into the room to avoid having to go in and out of the room.

If the CBR box is to be installed for lighting control, it is useful to use some kind of FMP bracket assembly product for pre-assembly and shorter installation times.

The active diffuser means that cold air streams in along the ceiling. Room air is injected into this and mixed with the fresh supply air so that after approximately 1.5 m the air is isothermic. Even if really cold air is used, the air doesn't create the low flows that are characteristic of other kinds of supply air diffusers. This means that the rooms don't become either draughty or cold.

The report shows that air streams upwards in the occupied zone and down along the walls, i.e. outside the occupied zone, which is defined as 20 cm from inner walls and 50 cm from outer walls.

Very few complaints
We have installed a great many diffusers in extremely varied spaces and our operation organizations have consistently had much lower levels of complaints about draughts than with other solutions.

No need for heating coils?
Because our solutions work with really low supply air temperatures, you may even find that you don't need to install a heating coil in the supply air aggregate, but can allow all heating to come from recycled air. In winter, when it is very cold outside, you have a low flow and high efficiency from heat recycling. This provides sufficiently high temperatures, and at low flows you can have REALLY low supply air temperatures.

Of course there must be some source of heat in the room to raise the temperature in empty rooms.