Induction Method of Air Delivery

Air Movement Pattern DiagramThe induction method of air delivery creates comfort. Each person in the room is warmed or cooled at the same rate, without feeling a draught.  The required temperature is reached more quickly and there are no uncomfortable hot/cold spots.

A modular air handling unit (AHU) is at the core of the system. The AHU is connected to a sustainable heating/cooling source and the main plenum ductwork. The AHU usually draws in air from the room being cooled or heated through a return air grille and duct. It treats the air as required to heat, cool, purify, mix with outside air and/or control humidity.

The AHU contains a high efficiency variable frequency drive fan motor. The fan motor creates an even, static pressure (potential energy), up to 300pa, throughout the whole plenum ductwork. This is known as static regain.

The plenum ductwork is connected to a series of flexible, small diameter, sound attenuated small ducts called mini ducts. The static regain ensures that the ductwork plenum is evenly pressurised. It ensures the ductwork plenum delivers the same amount of treated air to every mini duct. This in turn ensures that the mini ducts deliver the treated air evenly to where it is required. The static pressure (potential energy) is converted to velocity pressure (kinetic energy) as it is released through the mini ducts.

The mini ducts terminate in stylish and discreet air outlets.  Circular outlets have only a 50mm or 72mm opening. Linear and drilled outlet options are also available. The induction method of air delivery allows the air outlets to be positioned in ‘out of traffic’ areas in walls, ceilings, bulkheads, kick spaces and floors. This frees up floor and wall space as there is no need for radiators, large grilles and wall mounted units.

The smaller sizing of the mini ducts increases the speed at which the treated air leaves the system via the air outlets (The Venturi Effect). The increased speed delivers the small amounts of treated air into the room at low pressure (Bernoulli’s Theorem).

The Venturi Effect (Giovanni Battista Venturi 1746-1822)
When the duct size is reduced, the air inside flows more quickly.

Bernoulli’s Theorem (Daniel Bernoulli 1700-1782)
The quicker the air flow, the lower the air pressure in that flow.

The low pressure of the treated air stream draws room air continuously and imperceptibly back towards the air outlets. Air is slowly drawn from all corners of the room and gently mixed with the treated air stream. The room is warmed, cooled or purified evenly and there are no hot or cold or stale areas. There can be as little as 1oC variation from the thermostat setting throughout the conditioned space. Air movement is comfortable because it is virtually draught-free. The system is responsive and the temperature effect is felt very quickly.

The Constant Fan Option maintains this continuous, imperceptible movement of air even when the system is not heating or cooling. This helps keep room temperatures stable for longer, which reduces the operating time of the heating and cooling source and running costs.

You can increase energy savings by adding the high specification HEPS air purification module. This can reduce the fresh air requirement, meaning there can be less need to pre-heat or cool in-coming air.

This virtually draught-free air delivery allows increased temperature differential and thus, lower air volumes. Because no one can feel the air coming directly from the outlets, the air can be colder in cooling mode and warmer in heating mode. This same cooling or heating performance can be achieved using less air than other systems.

Create your perfect indoor climate today:
Call 0800 731 6352 or 01268 544530 or email