Return air location and height
I have a vintage 1985 tract home in San Diego County, Climate Zone 3B. I am planning for a kitchen remodel, drawing plans for a permit.
The return air is located in the kitchen, the kitchen is open to the main living room, so the room volume is not a problem. The return air is located in the far corner of the kitchen. The natural gas stove is about 8 ft away from the return air inlet. By the 2012 IRC the stove should be 10 ft away. I don’t/can’t plan to move it to get the distance.
The house has AC and the heater is 75,000 BTU natural gas I can slow the HVAC fan to a low of 875CFM or up to 1500CFM. The return air is from under the HVAC unit in the garage into the house. I can’t move the return air from the kitchen without running it out on to the roof or raising the roof. Using the 2012 IRC or 2013 CBC.
The question is – at what height should I set the return air intake at in the kitchen?
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Replies
Tim. Just out of curiosity... You will need to permit this remodel, correct? If so, the safe course would be to talk with your local building department. Maybe they will accept 8 feet (or not). They also can give you guidance on locating the return.
Hi, Yes I need a permit. We are also replacing windows and structural upgrades to the weak stucco shear walls at narrow walls. I think I can keep the 8 ft because I am not moving either the RA or the stove. What do you think is best for air quality? I wanted a well reasoned answer prior to talking to the Building Dept.
Tim,
Q. "At what height should I set the return air intake at in the kitchen?"
A. The height of a return air grille is not critical, so I would advise choosing a height that results in the shortest possible duct length.
Q: "What do you think is the best for air quality?"
A: replace gas stove with induction.
This does not address your code compliance question, but may be part of the solution to improving the quality of the air that does get circulated.
Hi, The electric stove is a good idea. Perhaps I should interlock the range hood with the HVAC, so if the range hood is on then the HVAC is off.
The duct run is just from under the HVAC unit thru a 2x6 wall so a 8 inch duct run to the interior floor.
Thanks for the comments.