Air Curtain advise

[whitetiger]

Just need some advise regarding the use of air curtains. I have an open space to condition and was wondering if, by using an air curtain would the heat load be calculated the same as if the space was in fact closed? If not, how much capacity should i expect to loose?

Cheers.

[Yuri B.]

Heat losses depend of course on how "open" the space being heated is.

[install monkey]

as long as they use the air curtain in fan only mode in summer then all will be ok,and shouldnt affect the cooling performance.
also in heating mode-if it ever goes cold in oz then it will aid the heating up of the room with the added capacity of the heatpumps

[Magoo]

Definitly worth the expense of installing above automatic doors etc, in shopping malls and the like. It is a fine art setting them up, with linear slot diffusers, use a smoke stick to get paterns correct. Air pressure balance between internal and external is important to get keep correct. I usually base losses on 20% of an open door area. You can expect around 20% of air spilling outside

[Simeonx1]

wouldnt the cool air get warmed up when its on heating aswell ?

[dogma]

Hey Whitetiger, Magoo is Right, in my opinion, the use of air curtains will dramatically decrease Heat ingress into the conditioned space by having open doors, In the meat works I used to work in in Oakey they had air curtains instead of the traditional meat curtains to separate the boning room from the freezers and holding rooms... the greater the pressure differential the greater the velocity. these worked on a door switch so when the doors were shut they would turn off. You can use a similar system in door ways that aren't constantly opening and closing. Like Magoo said earlier, velocities based on pressure differentials should be considered. A Traditional Heat Load estimate would be the same, factoring in outside heat ingress or losses due to and open door is more difficult.

[B G Scott]

The use of air curtains is not a guesstimate they need to be selected and designed for specific applications, especially if the air ingress is likely to have either or both a high temperature difference or a high humidity difference, vapour pressure differential can cause all sorts of complications if the internal space conditions need to be maintained with a close tolerance RH.
The outlet velocity will entrain air from both sides of the CURTAIN and the resultant mix will be introduced in some form into the conditioned space.
The natural exchange will invariable be an additional load on the A/C system which will need to be estimated, unfortunately if you are applying OFF the shelf air curtains the chance of getting good data from the manufacturer is limited.