Commercial air curtains an energy efficient HVAC system to ensure indoor air quality for retails stores warehouses, restaurant or retail space and prevent contamination and ensure a climate controlled indoor air quality from Flexiheat UKFlexiheat UK

Commercial Air Curtains


Commercial air curtains an energy efficient HVAC system to ensure indoor air quality for retails stores warehouses, restaurant or retail space and prevent contamination and ensure a climate controlled indoor air quality from Flexiheat UK

Commercial air curtain range from Flexiheat UK


Commercial air curtains, also known as commercial air doors are typically used in commercial premises or large retail outlets over the doorway or entrances to separate the internal temperature from the external ambient temperature via an air stream. Thus the internal air is separated from the external air, and not escaping when the door is open and no contaminants are let into building. We classify a commercial air curtain with the ability to have a horizontal mounting height of up to 4 metres or when installed vertically on both sides of the door up to 8 metres wide (up to 4 metres if installed on one side of the doorway or entrance), making them ideal for saving energy in a retail outlet for example with an open door policy whilst preventing heat loss and cold draughts.

Hotels, shops, commercial offices, reception areas, and sports centres are a few examples of typical installations.

Air curtains commercial – Energy savings

Air curtains work by causing an air barrier with an air stream –

A diagram showing the working principle of an air curtain by Flexiheat UK

Air curtain working principle -suitable for shops, offices, hotels or warehouses and other commercial premises – keeping heat in or even smoke out of doorways

Air curtains work by creating an efficient and invisible door or air barrier that keeps the heat inside by separating the air between the environments of two different air temperatures, which makes financial sense as they reduce heat loss and ensure reduced heating energy costs.

When installed in an air-conditioned shop, office, loading bays, hotels, supermarkets or cold storage facilities, air curtains can be even more effective for these different purposes, keeping the warm air out and the air inside the room at the correct temperature range.

Climate controlled commercial premises

They are manufactured to produce a warm welcome or even a cool welcome for entrances to commercial premises , depending on whether the commercial air curtain has a heater built into the model , or is a fan only type model (commonly referred to as an ambient air curtain model).

Clean indoor air

With any air curtain it is essential that the air curtains covers the entire door width to create a sealed entrance, either to keep the heated inside or cold air inside by keep the external environment temperatures from infiltrating into the building via the customers door entrance or openings and save energy usage.

The second important factor is the the jet or stream of air produced by the air curtain is powerful enough in range to get the airflow down to the doorways or entrances floor level.

Air curtain for commercial use

The most popular use for a commercial air curtain is to inhibiting heat losses typically from retail shops, banks, factories, food retail space or retail premises, a restaurant or healthcare environments and other commercial premises to create a warm welcome to customers or staff as they access a room environment via a door, doorways or entrance.

Air curtains for commercial applications or premises, powered by hot water or electric heaters or a non-heated version – ambient air and often used in shopping centres, stores, restaurant, or an airport from Flexiheat UK

Air curtains for commercial applications or premises, powered by hot water or electric heaters or a non-heated version – ambient air and often used in shopping centres, stores, restaurant, or an airport from Flexiheat UK

As well as other commercial premises where clean indoor air quality is a requirement – such as food service or food preparation controlled areas such as butchers or an abattoir – where keeping insects and dust out of the air is a requirement, especially in cold storage areas. This can be achieved with our commercial air curtains range.

We do three versions in this stylish air curtain range

W – Water heat exchanger (a 2 row heat exchanger) unit – heating the air flow .The heat output is relative to the hot water flow and return temperatures to the unit.
C – Without heater elements thus an “ambient air commercial air curtain” unit – taking the air temperature from the room’s internal air which they are installed in and passing it through the unit to form an air barrier or curtain
E –  Electric heated model – heating the air flow

Technical data for our air stream air curtain range for commercial applications from Flexiheat UK

Air Stream range of Air curtains – With the option of energy efficient “EC” fan motors or 3 Speed “AC” fan motors – IP20 protection class


This air curtains range – can be vertcially mounted or mounted horizontally above the doorway, with our versatile mounting brackets or hung from drop rods.

Commercial over door heater air curtain mounted horizontally over a doorway entrance

horizontal installation to provide warmth / comfortable environment for your entrance.

Commercial ambient air curtains

They keep the heated or cooled air contained inside the building when using a commercial ambient air curtain, which relies on other energy heating sources to warm the space, as they have no heater element.

This type of air curtain just produces a jet or barrier of air either over the door space when installed horizontally over the doorway, or you can have a vertical installation with the air curtains being installed vertically at the side on a wall of the door space, entrances or opening.

vertical commercial air curtain; vertical mounted door air curtains; vertical air curtain installation;

Vertical air curtain / Vertical door air curtain installation picture – “Airstream” range of ambient or heated air vertical air curtains that use a door switch or remote switch to activate the air flow when the doors are opened.


When used in a vertical configuration we can cover an entire door width of 8 metres for our ambient air commercial air curtain units, or 7.4 metres for our warm air heated commercial air curtain units when installed on both sides of the 

Mounting height and maximum width of door our air commercial curtains can achieve for for retails stores warehouses, restaurant or retail space to prevent contamination and ensure a climate controlled indoor air quality - Flexiheat UK

A Door can be covered up to 6 Metres wide – when installed vertically

Commercial air curtain heater – Commercial heated air curtains

These types of commercial air curtains are heated via a heating element. They are often referred to as commercial air curtain heater, which is either ;

Electrically heated commercial air curtain range

Due to the kW outputs of the models, they normally require an industrial three-phase electricity supply to power the heater elements within the air curtain or over door heaters, as some people refer to them.

Airstream electric powered commercial air curtain range from Flexiheat UK

Airstream electric powered commercial air curtain range – in Dark (RAL7016) or White (RAL9016) colour options

Our electric recessed air curtain range is very popular with hotels, shops and restaurants , as they can require a discrete air curtain above their access, doorways or revolving doors. See further down the webpage for more information on the recessed range of air curtains.

Hot Water Heated

Hot water heated air curtains (low pressure hot water), are very popular door heaters for commercial premises. The heater or heating element within the air curtain is fed by a wet heating system, which produces hot water for the door heaters heat exchanger, which takes this heat and transfers it into the warm air curtain and thus into the environment.

Download the Flexiheat Commercial Air Curtain “Airstream” Brochure

Download the Airstream commercial air curtain range manual

Energy efficient controls with thermostat

Our air curtain commercial range can be fitted with flexible control options  – A Wi-Fi type or a more capable controller that can be linked into a building management system if so required.Each of these controller can control up to 8 units.

Installing an external door sensor allows you to pick one of three automated functioning modes of control :

• Door (default mode): heating air supply or just ambient air supply, maintaining the selected temperature. Active only when the door is open.
• Room: heating or ambient air supply (air supply must be manually controlled) with temperature control. Enabled regardless of the condition of the door sensor.
• Door plus room: heating or ambient  air supply, maintaining the desired temperature control. Active based on the condition of the door sensor.

The HMI “EC” controller optimises the functioning of the commercial air curtain, assuring their continuous and dependable operation, and the device’s well-thought features a enable significant power efficiency and energy savings.

HMI EC Wi-Fi Controller for Airstream EC air curtains

HMI EC Wi-Fi Controller – so you can control the units from a phone or tablet.


Or our more capable unit, designated the “HMI EC”  which is weekly programmer, that can control up to 8 air curtains and can be coupled up to a building management system if so required with RTU Modbus protocol.

HMI EC Controller for our EC fan air curtains which can adjust fan speed with temperature control and can be connected to a BMS system.

HMI EC Controller – which can be connected to a BMS system via an interface with RTU Modbus protocol for easy integration with building management systems (BMS).


HMI “EC” Controller features

  • An advanced calendar is available for each day of the week.
  • Preset 3-level fan speed control – (on the “EC” models you can adjust each fan speed to an individual level to suit site conditions)
  • Build-in thermostat
  • There are three levels of heating power available.
  • A single controller can connect up to eight air curtains.
  • Modern and compact design
  • High contrast and a clear screen
  • Door sensor co-operation
  • BMS system compatibility

The full manual for our HMI “EC” fan controllers can be downloaded here –

Download the Flexiheat Manual HMI EC Controller

Recessed Air Curtains

We do a range of recessed air curtains which are very popular in large retail outlets and other commercial premises. Recessed air curtains models’ key benefits are that they are very discrete as they are covered and hidden in a suspended ceiling or bulkhead above the doorways for example. We have a dedicated webpage here – Recessed air curtains on our dedicated models.

air curtain recessed; recessed air curtain heater; recessed over door heaters; in ceiling air curtain; recessed mounted air curtain; recessed warm air curtain; ceiling recessed air curtains;

Recessed Air Curtain Heater or Ambient Air Curtain

Commercial air curtain heaters

Each air curtain or multiple air curtains can be controlled with one controller. The heater element of the air curtain can be switched off in the summer period. The controller can be mounted in a remote location, such as a reception area or next to the door or doorways. Our units are manufactured with a high quality fan , and the heater versions produce a nice warm welcome to offices, restaurants, shops, supermarkets or shopping centres etc.

Industrial air curtains

Finally, are our industrial air curtains range, these suit larger roller shutter doors, and can be mounted above the door (up to 8 metres installation height for our industrial ambient air curtains and 7.5 Metres for the heated industrial air curtains)or installed vertically up the door, again up to 8 metres installation height depending on the model type. These have their own dedicated webpage – Industrial air curtains

Air curtain commercial use

If you require any further support, information, advice, check stock or the latest offers of our commercial air curtains range, please contact us via our email form above on the website or call our UK business sales services team direct on 01202 822221. Sign up and follow us on Facebook and twitter for our latest news.