Commercial Kitchen Exhaust-Make up system- Controls

[mehdikardehi]

Hi All,

I am designing the exhaust of a commercial kitchen and I am thinking to makeup 80% of the exhaust requirement with evaporative cooler and the rest of that air to be provided from restaurant enclosure...want to run the evap unit in fan mode only during winter which is minimum of 0°C here

2 quick questions
- I need to have negative pressure inside the kitchen all the time. Shall I write a comment in my design saying that the evap unit can't be turned on when the exhaust is off or I need to provide some sort of controls for both fans? (I am looking for the cheapest option)
- To save energy both fans will be variable speed. How to control them in a way that it's negative inside all the time? Shall I trust the operator?

Regards,
M

 

[berkshire]

interlink the fan from the swamp cooler to the exhaust fan , and leave the water pump on a manual control.
B.E

You are judged not by what you know, but by what you can do.

 

[SAK9]

Your concept seems about right.You would need to heat the make up air in winter.

I would put in a speed selector switch for the exhaust fan next to the hood so that they can turn down the speed to a preset low( to save energy when not cooking. This low would be decided by the minimum evap cooler air flow to maintain comfortable conditions within the kitchen when not cooking.The evap cooler fan would need to track this and slow down in tandem to keep the room negative and save heaps of energy in winter.The set points would need to be manually determined during the commissioning process.

 

[mehdikardehi]

thanks for the advice....Is this a good solution for kitchen? let me know if you are thinking of a better solution for kitchen exhaust

 

[berkshire]

I would size the makeup air for 95% And make sure the kitchen doors are tight. If you have a pass through, at 20% you will have a gale across the pass through counter.
B.E.

You are judged not by what you know, but by what you can do.

 

[mehdikardehi]

Thanks berkshire....good point

The kitchen has serving areas to the bars on 3 sides and I was thinking of using those openings for my air passage

I was thinking to suck some conditioned air from restaurant to make the conditions more comfortable for the kitchen staff specially during winter

Do you think it's not a good idea?

 

[berkshire]

SAK9 seems to have the best idea.
Your concept seems about right. You would need to heat the make up air in winter.

Bear in mind that a kitchen with stoves, ovens, and other sources of heat, usually has the opposite problem, trying to get rid of the heat. So you may not have to re-heat that much.
B.E.

You are judged not by what you know, but by what you can do.

 

[mehdikardehi]

Cheers, good advice

 

[chicopee]

I have always been a proponent of a push pull ventilation system over kitchen cooking appliances. Such a system saves on A/C and heating of the rest of the restaurant and bar.

 

[cry22]

try this if your system is of good size.
A bit expensive, but the best out there.

http://www.melinkcorp.com/

maintain 500 FPM minimum in your exhaust per NFPA 96

 

[mehdikardehi]

good stuff....how do you connect your makeup air with such a hood?

 

[cry22]

through a vav box

 

[Drazen]

with three sides open, you should draw all air from restaurant area.

 

[mehdikardehi]

There is a makeup fan to avoid this Drazen

 

[Drazen]

the only reason to put make up in kitchen is if you cannot avoid drafts in air transition. as you seem to do not have such problem at all, putting make up in kitchen instead of fully using restaurant air is pretty large waste of money.