Dining facility HVAC

[txdilbert]

Is it common practice to provide direct mechanical cooling for a kitchen area in a dining facility? Or, is kitchen worker comfort generally accomplished by air being transfered to the kitchen from the dining area because of the negative pressure in the kitchen?

Would it be a bad idea to provide direct cooling for just the kitchen to ensure 85 or below? What is the best control scheme to accomplish this and avoid system hunt?

 

[AbbyNormal]

my experience is to put the kitchen on its own system

if it is air conditioned I shoot for 80F and 60% during prime time

You can allow air transfer from the dining room system to account for some of the make up air, typically a kitchen make up air unit is 70 or 80% of the hood exhaust

Depending on where you are maybe you use evaporative cooling in the kitchen.

Maybe the short order cook does not have a green card and will not complain if it is 85 and humid in the kitchen.



Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[txdilbert]

Abby,

When you say you would put the kitchen on its own system, you mean that you would provide a make-up air unit for the kitchen that would both heat and cool? The unit would have humidity control, correct? Humidistat mounted where?

I've seen some kitchen MUAHUs designed for a minimum discharge air temp. of 60 - what is your experience with this and does it lead to humidity complaints?

Anyone else have any insight?

 

[trashcanman]

Makeup air units for kitchen hoods are usually filtered only. Exceptions could be in severe winter climates or very hot/humid climates. I agree with Abby. Use a separate unit for the kitchen and separate one for dining. The outside air required for the people in the dining area can be drawn into the kitchen to make up the net exhaust air from the kitchen. Example: Dining area requires 500 cfm O/A. Kitchen exhausts 2000 cfm, auxiliary air to hood is 1600 cfm. Net kitchen exhaust = 400 cfm. This 400 cfm can be drawn from the dining area.
Thus, 400 cfm of dining room temperature air is drawn into the kitchen, not raw outside air.

 

[AbbyNormal]

Abby,

When you say you would put the kitchen on its own system, you mean that you would provide a make-up air unit for the kitchen that would both heat and cool? The unit would have humidity control, correct? Humidistat mounted where?

I've seen some kitchen MUAHUs designed for a minimum discharge air temp. of 60 - what is your experience with this and does it lead to humidity complaints?

Anyone else have any insight?

I am in a year round cooling environment. I typically would supply un tempered make up air probably 60 to 70% of what the hood exhausts through a back supply plenum.

The kitchen will have its own cooling system and perhaps this system draws in some fresh air as well, and makes up some of the remianing 30% of the exhaust air but not all of it.

The dining room system will have a fair amount of fresh air in it to ventilate for all the people. The fresh air in the dining room system also replaces what is exhausted out of washrooms. Because the kitchen is still running at a slight imbalance, air from the dining room will travel to the kitchen, and this movement of air tends to keep odors in the kitchen and out of the dining room.

You can sometimes have a gas fired unit to temper up the make up air in the winter and perhaps this air is introduced through ceiling diffusers and the kitchen basically heats itself.

Dependeing on where you live perhaps the make up air unit could have an evaporative cooling section on it, or even a DX coil, and then you would be conditioning all the make up air and using it to attempt to keep the kitchewn cool. It is economical if it works, with the evaporative cooler, perhaps it wastes a lot of energy with the DX option.

If it was a small facility, and the hood was say not much more than 6 feet long, sometimes I have used one unit for both the dining area and the kitchen but you do not want to be drawing return air from the kitchen. The make up air volume supplied at the hood is reduced and all the make up air is brought in through the HVAC.

You have no return from the kitchen, the air is exhausted up the hood.


Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[AbbyNormal]

In my second last sentence I meant to say and the "remaining make up all is brought in through the HVAC"

Read twice and post once.

Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[AbbyNormal]

lol air not all

Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[txdilbert]

Excellent. Thanks for the response. I have a much better idea about how I will approach this.