The Question of Kitchen Cross Currents

June 29, 2009
/ Print / Reprints /
ShareMore
/ Text Size+
Al D'Ambola

With smoke you can see them, with your nose you can smell them, and unfortunately for the workers in restaurant kitchens, they can feel the heat. Cross currents are air patterns that enter a capture hood and push the radiant heat, smoke, and odors from the cooking surfaces away from the hood, and into the kitchen.

All too often we are called in to evaluate problem restaurants where the hood is not capturing the heat or smoke from the cooking surfaces. One of the first things to look at when diagnosing a capture hood is the possibility of cross current interference. Typically this is caused by improper placement of supply registers for the a/c unit that are too close and above the plane of the hood.

As the cold air comes out of the supply registers, which are not balanced for velocity, the air now enters the capture zone of the hood. This causes tremendous turbulence and the cold dense air can push the radiant heat and smoke outside of the hood, causing extreme comfort and IAQ issues for the restaurant employees, as well as a huge waste of energy for the restaurant owner.

The supply registers should be a minimum distance of 10 feet from the hood and, most critical for side wall supply registers, be at an even plane with the hood. Unfortunately, this is not the norm. Consider changing the type of ceiling supply registers that will throw the air away from the capture hood, a two-way versus a four-way or side wall register that will allow you to direct the air away from the hood. This will reduce the turbulence and go a long way toward keeping the radiant heat and smoke from the cooking surfaces in the containment area of the hood on which you are working.

What if the restaurant cooking area is located in the dining area? Cross currents can push smoke and heat outside the hood and cause a host of odor and comfort issues for the patrons, and a nightmare for the restaurant. Supply a/c registers placement is extremely critical.

So if you are working in a retrofit application, remember, cross currents caused by the a/c unit could have a major impact on air quality, utility expense, and hood performance.

Publication date: 06/29/2009

Did you enjoy this article? Click here to subscribe to The NEWS Magazine

You must login or register in order to post a comment.

Multimedia

Videos

Image Galleries

2014 Energy Efficiency Forum

Highlights from the 25th annual Energy Efficiency Forum in Washington, D.C.

Podcasts

NEWSMakers: Mark Satterfield

Mark Satterfield, founder and CEO of Gentle Rain Marketing Inc. and author of “The One Week Marketing Plan” talks about his book and the importance of HVAC blogging. Posted on Sept. 19.

More Podcasts

ACHRNEWS

NEWS 09-15-14 cover

2014 September 15

Check out the weekly edition of The NEWS today!

Table Of Contents Subscribe

Venting R-22

The NEWS reported that a man received prison time for venting R-22. Should EPA step up enforcement?
View Results Poll Archive

HVACR INDUSTRY STORE

plumbing-hvac.gif
2014 National Plumbing & HVAC Estimator

Every plumbing and HVAC estimator can use the cost estimates in this practical manual!

More Products

Clear Seas Research

 

Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.

DON'T MISS A THING

Magazine image
 
Register today for complete access to ACHRNews.com. Get full access to the latest features, Extra Edition, and more.

STAY CONNECTED

facebook icontwitter iconyoutube iconLinkedIn i con