In its simplest application, an air curtain is a continuous broad stream of air circulated across a doorway of a conditioned space. It reduces penetration of insects and unconditioned air into a conditioned space by forcing an air stream over the entire entrance.
Air curtains’ effectiveness in preventing infiltration through an entrance generally ranges from 60 to 80%.
An alternative definition of an Air Curtain is: “A directionally controlled airstream, moving across the entire height and width of an opening, which reduces the infiltration or transfer of air from one side of the opening to the other and/or inhibits flying insects, dust or debris from passing through”.
Although air curtains at the entrance to many shops and public places are the most visible and well-known application to the General Public; there are many and varied Air Curtain Applications across the domestic, commercial and industrial sectors.
Unheated air curtains consume very little energy (consumption being limited to the power of the fan only). Heated air curtains vary hugely in power consumption depending on the model selected but in most cases the power consumed can me largely offset against the energy saved by partially excluding the negative effects of the outside environment.
‘Ambient’ (Unheated) Air Curtain Applications – Air Curtain Applications may not necessarily require the air stream to be heated or chilled. The majority of air curtains provide an unheated or ‘Ambient’ airstream. The purpose of the air curtain is simply to provide a barrier between 2 environments. At its simplest the barrier is between indoors and outdoors and may achieve any or all of the following:-
- Heat loss prevention / energy savings – During winter months this will prevent heat loss from the heated internal side of the barrier to the external environment.
- Heat gain prevention / energy savings – During summer months this will prevent heat gain from the external environment to the internal, air-conditioned side.
- Internal environment control – Prevention of ingress of car fumes, airborne dust, flying insects, noxious odours, cigarette smoke and other pollutants to the controlled commercial, domestic or industrial environment.
One of the most common air curtain applications for the ambiant type of unit is for cold store and large chilled environments where keeping the cold expensive air in and the dirty relatively warm air out is key.
Heated Air Curtain Applications may be split into 3 categories – Electrically Heated, Hot Water Heated and Gas Heated. All types are available across the whole range of industrial / commercial / domestic applications with capacities ranging from under 5kW of heating power to over 100kW. They are available in horizontally mounted or vertically mounted formats and suitable for doorways ranging from 2m in height to 6m or more. The larger sizes are available equipped for either standard hot water feed or high-temperature hot water feed making available very high heat outputs.
- Electrically Heated Air Curtains – Electrically heated air curtains are necessary wherever a centralised hot water system is not in place and the only power source is electricity. These are widely used in medium and large-sized commercial and industrial applications and are also particularly suited to domestic and small commercial applications. As fossil fuel usage reduces and renewable energy sources begin to predominate, the incidence of gas-fired domestic boilers will decline drastically.
- Hot Water Heated Air Curtains – Hot Water heated air curtains are applicable wherever a centralised hot water system is available. The power source for heating the water can be selected from any available source – Electricity, Natural Gas, Propane, Diesel, Oil, Renewables etc. The cost and efficiency of delivering hot water to the Air Curtain must be considered carefully when making a selection. The hot water pipes will have to be heavily insulated to maintain overall efficiency however if heat losses are to an already heated environment then they might be tolerated as they will mitigate the overall heating cost.
Gas Heated Air Curtains – Gas heated air curtains require a large volume gas suppy available – this can be either Natural Gas or Propane. Comprises a multijet gas burners and a heat exchanger combined with a high velocity air flow flow a separate fan. Intrinsically efficient but most cost effective on larger or multiple applications due to the specialised maintenance required.
Puravent’s range of Air Curtains covers Ambient, Hot Water Heated and Electrically Heated options. Horizontally mounted machines (Vertical air curtains) are available to provide curtains from up to 2.5m, 3m, 4m, 5m or 6m from floor level. Vertically mounted machines (Horizontal air curtains) are available at up to 6m in height (supplied as 2 stackable 3m high units).
The complete offering runs into hundreds of options so if you require any assistance please do call us to discuss your requirements on 01729 824108. Alternatively email through your enquiry to email@example.com or follow us on facebook