Air Diffusers for HVAC Systems in Georgia
An air diffuser is the final air distribution element of a ventilation and air conditioning system, through which supply air is spread into a space in a specific direction and pattern. The NB Group range includes round and square ceiling diffusers, slot diffusers, swirl and jet models.
What is an air diffuser?
The main task of a diffuser is to distribute the air received from a ventilation duct correctly into the space. Simply supplying air to a room is not enough - it has to be spread in such a way that it reaches the occupied zone and is distributed as evenly as possible.
A diffuser can be used for air supply, in certain models for air return, in cooling systems, in heating mode and in centralised ventilation systems. For example, the NB Group HDTA round ceiling diffuser is intended both for distributing conditioned air evenly and for extracting used air.
What types of air diffuser are available at NB Group?
The current NB Group category includes: HGA disc valve; HDTA round ceiling diffuser; HDKTA square ceiling diffuser; HSD slot diffuser; HTD turbulent diffuser; HGSD secret slot diffuser; HSSWD ceiling swirl diffuser; HSWD adjustable ceiling swirl diffuser; HDYSD four way ceiling diffuser; HIKD diffuser for high ceilings; HDD jet diffuser; NJN jet nozzle.
A diffuser should therefore not be selected by visual shape alone - different models have different air distribution principles and fields of use.
How to select an air diffuser
1. How much air has to pass through the diffuser?
First you need to know the amount of air to be supplied at the specific point. Passing a large airflow through an undersized diffuser can increase air velocity, noise, pressure loss and the risk of a strong draught in the occupied zone. The size of a diffuser should therefore not be chosen only according to the opening in the ceiling.
2. Why does ceiling height matter?
A diffuser has to deliver air down to the zone where people are, so ceiling height is directly linked to the required air distribution characteristics. For example, the NB Group HDTA round diffuser is intended for spaces of approximately 3 to 4 m, the HGSD secret slot model for ceilings of about 2.5 to 4 m, the HTD turbulent diffuser is recommended for spaces of at least about 3.5 m, and HIKD is intended for buildings of about 3.8 to 15 m.
Round or square ceiling diffuser?
Both types are used to distribute air from the ceiling, but they differ in construction and in the shape of the air spread.
The NB Group HDTA round ceiling diffuser is used to distribute conditioned air evenly and can also perform an air return function. The standard version of the HDKTA square ceiling diffuser distributes air in four directions, while one, two or three way configurations are also possible if required. The choice should be based on the shape of the space and the required air direction.
What is a slot diffuser?
A slot diffuser is a narrow linear air distribution element, used particularly often where, alongside the technical function, a minimalist interior look also matters. The NB Group HSD model can be used both for supply and return systems. It is produced in 1, 2, 3 and 4 slot versions.
What is a secret slot diffuser?
A secret slot diffuser is used when the air outlet should be as unobtrusive as possible in the interior. The frame of the NB Group HGSD model is hidden in the ceiling and only a thin linear slot remains visible. This type can be of interest in modern offices, hotels, premium residential spaces and minimalist interior projects.
What is a turbulent or swirl diffuser?
A turbulent diffuser distributes air with a rotating, swirl type flow, which supports intensive mixing of air in the space. The NB Group HTD model is available with both fixed and adjustable blades. Diffusers of this type are used in tall spaces, for example shopping centres, cinemas, sports halls and conference areas.
What does an adjustable swirl diffuser mean?
In NB Group HSWD models the position of the blades can be changed, which allows the air direction to be altered. This is particularly important when the same system is used for cooling in summer and heating in winter, since cold and warm air behave differently in a space.
What is a jet diffuser?
A jet diffuser is used when air has to travel a relatively long distance. The NB Group HDD model is designed for spaces with high ceilings where air has to be delivered far under high pressure. Such a solution can be used in large shopping centres, sports halls, cinemas and conference halls.
Are a diffuser and a grille the same thing?
| Diffuser | Grille |
|---|---|
| Designed to distribute air into the space in a defined pattern | Often serves air supply or extraction and direction control |
| Usually mounted on the ceiling | Can be on a wall, ceiling, door, floor or duct |
| Round, square, slot, swirl and jet types exist | Single deflection, double deflection, egg crate and other types are common |
The choice should be made according to the air distribution required by the project, not by the name.
What is a plenum box used for?
Many ceiling and slot diffusers do not connect directly to a ventilation duct - a plenum box can be used with them, distributing the air from the duct across the whole surface of the diffuser. The NB Group HSD slot diffuser is intended for direct mounting on a plenum box.
What are the most common mistakes when selecting an air diffuser?
Choosing by design only
A diffuser is part of the interior, but first of all it is a technical air distribution component.
Ignoring ceiling height
The same air distribution solution does not always suit a tall hall and a 2.7 metre office.
Selecting by opening size only
The real amount of air also has to be known.
Not considering air direction
Directing cold air straight into a permanently occupied working or resting zone can create discomfort.
What information is needed to select a diffuser?
Before selection it helps to know:
- how many m3/h have to be supplied;
- whether supply or air return is required;
- the floor area of the room;
- the ceiling height;
- the installation location of the diffuser;
- the distance over which air has to be spread;
- the required direction of distribution;
- whether the system is used in heating and cooling modes;
- how important the noise level is;
- whether a damper is required;
- whether a plenum box is required.
With this data the type, size and air distribution principle of the diffuser can be selected correctly.
Air diffusers at NB Group
NB Group supplies air diffusers for ventilation and air conditioning systems - from small and medium height spaces to high ceilinged retail, sports and public buildings.
The range includes round diffusers, square ceiling diffusers, slot diffusers, secret slot models, swirl and turbulent diffusers, four way diffusers, high ceiling diffusers, jet diffusers and jet nozzle type solutions. NB Group branches are located in Tbilisi and Batumi.
Frequently asked questions
An air diffuser is the final air distribution element of an HVAC system, which spreads supply air into the space in a defined direction.
Most diffusers are mounted on the ceiling, although depending on the type and system another solution can also be used.
You need to consider the amount of air, the ceiling height, the size of the space, the required spread distance, the air direction and the heating or cooling mode.
A slot diffuser is a narrow linear air distribution element. The NB Group HSD model exists in supply and return versions and can be made with several slots.
It is a diffuser that distributes air with a swirl effect and is used for intensive air distribution in a space.
For high ceilings the HTD, HIKD, HDD or another suitable long throw model can be considered, depending on the specific height and required airflow.
Both are air distribution elements, but a diffuser is mainly used to create a specific spread pattern in the space, while grilles also have different supply, extract and transfer functions.
NB Group branches are located in Tbilisi and Batumi. Contact us for a consultation.
