Thread: AC return in kitchen

Had a Air Return in the kitchen today. I found a thread from earlier this year but there was no conclusion as to why it is prohibited. Here's the code. Some suggested for preventing noxious odors from circulating others prevention of kitchen fire spread. Can anyone give me a difinitive reason for this?

Thanks!!

From the IRC.
- SECTION M1602
- - RETURN AIR
- - M1602.2 Prohibited sources. Outdoor and return air for a forced-air heating or cooling system shall not be taken from the following locations:

- - - 4. A closet, bathroom, toilet room, kitchen, garage,
mechanical room, furnace room or other dwelling unit.

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Gas appliances, smoke and odors come to mind.

Now you're just being picky Rick. How else are the homeowners supposed to get the smell of curry to the upstairs bedroom?

My old home had one at or near the kitchen. It was along a wall that started the kitchen. I never considered it to be a problem. Now the thermostat was an issue and it was relocated.

To my understanding, you CAN have a return air sized to match the supply air in those prohibited locations, just not a central type return that would serve more than that room.
I don't know the specific reasons, but those reasons Rick sited would also be my guess.

Originally Posted by Jim Luttrall

To my understanding, you CAN have a return air sized to match the supply air in those prohibited locations, just not a central type return that would serve more than that room.
I don't know the specific reasons, but those reasons Rick sited would also be my guess.

Jim:

The answer lies in the exceptions of M1602.2:

2.2. The volume of supply air discharged back into the same space shall be approximately equal to the volume of return air taken from the space.

Aaron

Originally Posted by Jim Luttrall

To my understanding, you CAN have a return air sized to match the supply air in those prohibited locations, just not a central type return that would serve more than that room.
I don't know the specific reasons, but those reasons Rick sited would also be my guess.

Jim - I don't see any exceptions in the IRC to the prohibition on return air coming from kitchens, baths, garages, etc. See M1602.2 #4. You may be referring to the exception listed for #3 having to do with the minimum volume requirement.

I don't understand the problem with a return in the kitchen.

If air supplies the kitchen then it will return form the kitchen back to the main unit through some return, whether it be from within the same room or another. The kitchen air will mix with the whole system no matter.

Kitchen

- Smoke

- Fire

- Odors

- Grease

- Moisture

Bathroom

- Odors

- Moisture

Jerry,

I agree with your response to this post.

All of those smelly things ARE generated in the Kitchen and Bath, BUT they still get back to the main air handling unit though a return air grille (located somewhere) and get re-distributed throughout the house.

So.... Back to the question -- What's the purpose of not having a return in the kitchen when the air from the kitchen will still return, get mixed with all the house air and smell up the whole place anyway?

John and Aaron, sorry for the confusing wording in my post earlier. (I guess I should use the preview feature to see how well I convey my thoughts before posting)
Aaron posted the exception that is applicable to allow individual room returns, I just was to lazy to look it up.

The second sentence of my post was intended to reply to the original question as to why a specific location is prohibited.

I found a thread from earlier this year but there was no conclusion as to why it is prohibited

As we all know, the code does not usually give reasons as to why the code allows or prohibits things, and as such, I can't speculate with any degree of accuracy about the reasons the contributors agreed on a particular path.
Thus my statement:

I don't know the specific reasons, but those reasons Rick sited would also be my guess.

Ken,

I don't think the primary concern is the "smelly" things. Unless you have one of those guest restrooms right off the breakfast room. I call it the pork and beans factor.

Personally, I think the reasoning is more for smoke, or possible gas fumes from say like a range or a cook top.

If something catches fire say in the kitchen and your off upstairs taking a nap, do you want that smoke being sucked into the return and blown into your bedroom while your asleep. I don't think so.

Remember now you pulled the batteries out of the smoke alarms because of that damn chirping noise and now you don't have a clue that the kitchen is on fire or filling with smoke . Your just sleeping away dreaming of Britney Spears on the MTV awards.

Then their is the all of years of deep frying all that catfish and chicken on the kitchen counter tops. You can just imagine how all that grease laden particles that have been sucked into the system and has been deposited on the evaporator coils. Plus the dishwasher and the boiling on the stove is putting excessive moisture off. None which is great for the HVAC system.

The return from the garage should be a no-brainer.

Rick

Thanks for the input everyone!

Keeping the central return out of the kitchen works fine in an older house but what happens with an open floorplan when there are few walls to seperate the kitchen? In my home the return is but a few feet from the kitchen granted it's about as far away from the stove as you can get.

Rick, if your upstairs sleeping with something cooking in the kitchen that starts a fire and you've pulled the batteries on the detectrors maybe the smell of smoke in the bedroom might just wake you from your Brittney dreams to save your butt.

Rick,

Originally Posted by Rick Hurst

Ken,

. Your just sleeping away dreaming of Britney Spears on the MTV awards.

The return from the garage should be a no-brainer.

Rick

Did you hook-up that YAMAHAW turn table in the garage?