Saving Energy with Warm Air Curtains
Air curtains are a simple and efficient form of high–level heating.
In a nutshell, an air curtain acts as an “invisible door”, keeping heated or conditioned air in, by using high speed, high airflow.
They are ideal for the entrances of commercial buildings such as shops or offices, and provide a curtain of warm air by blasting hot air down from the unit to the floor. This creates an insulation barrier, preventing the exchange of hot and cold air and eliminating drafts, whilst at the same time repelling insects and air pollutants such as pollen, dust and traffic fumes.
In a nutshell, an air curtain acts as an “invisible door”, keeping heated or conditioned air in, by using high speed, high airflow. Warm air curtains can cover doors of up to 6m and are designed to help disperse warm air gently in all directions, from top to bottom. As such they are an excellent way to keep an environment clean and comfortable, providing a consistent temperature all round and preventing energy loss — thereby reducing heating bills.
Whilst they are not capable of blocking heavy draughts (no more than 3m/sec) or pressures which are excessively high or low, they are an effective back–up to main heating systems, warming up and/or filtering any air that does get through. In summer they can run on fan only mode to keep rooms cool.
For Heating, Ventilation and Air Conditioning (HVAC) applications, air curtains can incorporate filtration and can be used for the reverse effect, i.e. to seal chilled areas, keeping cold air in, for example in cold store areas – a common application being for food storage.
Air curtains must be installed carefully in order to reduce the risk of fire, electric shock or injury. Therefore fitting and electrical wiring must be carried by a qualified person, with adherence to all relevant quality standards, including those related to fire–related construction.
In addition, the unit’s operation can affect the combustion airflow required for safe operation of a hot air curtain. Safety standards which should be consulted in order to avoid this include the National Fire Protection Association (NFPA), the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE).
It is also essential to exercise extreme caution when drilling into walls or ceilings in order to avoid damage to electrical or other wiring.
The position and coverage of warm air curtains is vital, since its performance can be affected by factors such as height, output, air volume, and even the design of the building. An air curtain must cover the entire width of the door opening, with a strong enough air flow for the height.
In HVAC cases, where air conditioning is incorporated, it is also important to consider where the air drawn into the unit will come from as there is a danger of sucking in pollutants from dusty or dirty roof areas.
Even though an air curtain can be bought “off–the–shelf”, it may be necessary to find a manufacturer who can offer a bespoke unit which has been tailored to meet specific building requirements.
And it needn’t be an eyesore either. Today’s emphasis on the environment and energy–saving initiatives continues to strengthen, which has encouraged manufacturers to develop more aesthetic products, designed to complement and blend into the surroundings.
Overall, air curtains are a fast and effective heating accessory offering both commercial and environmental benefits.Start of page