Air Curtain

Looking to use an air curtain for a mobile vending unit.  Has anyone had any luck on using one and/or making their own? I am afraid the standard commercial unit will blow too much air.

Yes I made one for my concession trailer service window. It was very easy to do. I drilled some small holes in the counter top and mounted a small blower motor under the counter. Then wired it to a on/off switch and a plug in for power. It doesn't take alot of air moving for it to work. We never had any problems with fly's after installing the blower.

If you don't mind me asking.... How wide was your window? What size were the holes and how far apart were they? And lastly what size blower did you use?

Thank you for all your help!

mikejames533


Yes I made one for my concession trailer service window. It was very easy to do. I drilled some small holes in the counter top and mounted a small blower motor under the counter. Then wired it to a on/off switch and a plug in for power. It doesn't take alot of air moving for it to work. We never had any problems with fly's after installing the blower.

 
Interesting, can you post a picture of your air curtain? I have been searching for a 12V DC air curtain but no luck and a 110V unit is unnecessary power usage.

Reese,
The same fan your using for your exhaust system ( isn't it 12 volt don't remember) would work. Just focus the air using the same type elongated funnel  that is on a household air duct off the main trunk. As handy as you are you could build one.
 
But all that said I have an expensive air curtain that I bought on Ebay some time ago and never installed. And I didn't install it because I use my exhaust fan to draw air into the trailer in order to cool it in the summer. If you have an air curtain and the exhaust fan running your exhaust fan will over power the air curtain I'd think. Maybe not?
jack

Would the air curtain be for the serving window to keep out bugs or would it be in front of the cooking area to separate you from the heat?

Dr of BBQ


Reese,
The same fan your using for your exhaust system ( isn't it 12 volt don't remember) would work. Just focus the air using the same type elongated funnel  that is on a household air duct off the main trunk. As handy as you are you could build one.

But all that said I have an expensive air curtain that I bought on Ebay some time ago and never installed. And I didn't install it because I use my exhaust fan to draw air into the trailer in order to cool it in the summer. If you have an air curtain and the exhaust fan running your exhaust fan will over power the air curtain I'd think. Maybe not?
jack

 
The exhaust fans are 110V. But good point, the suction from the exhaust would likely make the air curtain useless.

Reese,
I'm not 100% sure of that but that was my thought. And I hate the fact the within 3 days of the Illinois State Fair coming to town we get a ton of flies here. I have always thought it was because they come in with all the livestock that is brought to the fairgrounds. Build a screen or have one built the you can slide open or left up to serve your customers. It won't have to run in the same track but anything that offers some coverage and allow air movement will help.

Dr of BBQ


Reese,
I'm not 100% sure of that but that was my thought. And I hate the fact the within 3 days of the Illinois State Fair coming to town we get a ton of flies here. I have always thought it was because they come in with all the livestock that is brought to the fairgrounds. Build a screen or have one built the you can slide open or left up to serve your customers. It won't have to run in the same track but anything that offers some coverage and allow air movement will help.

 
I have a window with sliding screen installed but do not want to keep closing it over and over while serving. The screen slides to the side versus up. I think I will split the screen in half and make the bottom portion flip up so I can just let it flap down close quickly versus sliding.

I think I posted the link below before, and its probably a bit late if you already have your hood installed, but the location of the make up air can be of great assistance in not wasting your A/C, and help keep from pulling the outside air in.  In a very small space, the examples are not as applicable.  I think the rear discharge back supply is probably the most effective, as using an air curtain type return air on the hood itself is too disruptive to the air flow around the burners.  Here's a link to the site:
http://www.fishnick.com/ventilation/designguides/
The different make up air approaches are in the design guide 2.
As far as a fan is concerned for the window I'd recommend a cross flow fan, you can google 12V cross flow fan and find a lot of hits.  They are quiet small and will help on a small service window type application.  
Hope this helps.

I used a fan like this (http://www.amazon.com/Day.../ref=pd_sim_sbs_hi_3), but got it at a local place. My trailer is in storage 200 miles away right now. So I can't get pic's at this time. Our serving window that opens is about 18" wide. Our 4' hood system didn't effect the air curtain in the trailer.  It just takes a small amount of positive air flow to keep the fly's out! I can't remember the exact bit size I used but maybe 5/16 or so. You could mount a fan on a scrape piece of plywood and see what size holes works for you. You could also hook a fan up to a longer/thin air great to give a wider flow of air if your window is wider.
 
Hope this helps,
Mike

Ok I was thinking about this today here is how it might work and still allow the air flow for non air conditioned trailers and trucks. You'd need to mount it above and on the outside of your window. It won't take a lot of pressure/wind flow or what ever you'd call the stream to keep flies away. If you could mount it so that the air stream didn't blow hard all the way to the bottom of your window you would be decreasing the area that flies had to come in your service window. I hope you can understand my point. I'll think about how to word it better and edit my post if I can come up with a better explanation LOL
jack
PS it could be on the inside also just limit the power of the air current and you could still draw air from the outside.

How about a 12Vdc Dayton blower fan connected to a perforated pvc drain pipe cut to your length. It could be removable and covered with a lite weight housing of your choice. The blower is around 100.00 bucks and the pipe is cheap at lowes. I did this for a Glass Art shop, the furnace was too hot to stand in front of, theirs blew the air up and made it much more comfortable. I used duct tape to block 3 of the 4 rows.

You guys are way over thinking this! Keep your air holes on the inside of your trailer just a few inches from your serving window.
Our trailer has  roof air. And with the roof air on or off the air curtain worked great. Weather the 4' hood was on or off the air curtain still did it's job...
 
Mike

mikejames533


You guys are way over thinking this! Keep your air holes on the inside of your trailer just a few inches from your serving window.
Our trailer has  roof air. And with the roof air on or off the air curtain worked great. Weather the 4' hood was on or off the air curtain still did it's job...

Mike

 
Mike I think your missing the point. A few of us use or exhaust system fans to suck air through the unit in order to cool it. If an air curtain impedes
the flow of air into the truck or trailer it shuts off that flow. And the thought (my thought) was if it (air curtain) doesn't slow the air flow into the unit
how will it keep the pest out?

Dr of BBQ I got your point. But that has nothing to do with the author of this threads questions...

Mike this was a part of the original question "I am afraid the standard commercial unit will blow too much air."
 
I'd have to ask why if there wasn't some concern about bringing air into the unit for cooling?
 

"I am afraid the standard commercial unit will blow too much air."
 
And I take it to mean he was looking at a unit that was meant more for door ways and moves to much air for a service window. He never mentioned using his hood system to help cool his trailer.

Lol Could be maybe he will post again and then we will know. I didn't know they made Air Curtain for doors vs windows.

Thanks guys for all your responses....they were extremely helpful. I was concerned with the amount of air blowing for the service window and not wanting to feel like I was in a wind tunnel lol. But hopefully everything else that was posted helped someone else out!

Mikejames- I will definitely be trying out your idea very soon! Thanks for the input.