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-   -   It's hot outside. Keep the exterior doors and windows closed if running the A/C? (

Taylor Crockett 07-06-2008 05:32 PM

It's hot outside. Keep the exterior doors and windows closed if running the A/C?
I guess, if I could sum it up, I want to know if it's hot outside and the exterior doors and windows are open, will the A/C be less effective? C'mon, who doesn't know that if you close the doors the A/C will work better and blow colder? My roommate.

Okay, so I have a little rommate problem. He likes to leave the doors open because he likes fresh air. But even with the doors closed, you can barely feel the A/C during the day. I live in Pasadena (Los Angeles), CA.
I have a split-system A/C unit with an outdoor condenser and an indoor air handling unit in the attic. My return air vent, (which is also called air conditioning supply vent?), is on one side of my house. The house is split in half by 2 doors. One side is the living room and kitchen, with one long wall and 2 doors separating the house. With the other side having 2 bedrooms, the bathroom, and a hallway.

Bathroom| - - - |/ door to: Living Room
Bathroom| - - - |
Bathroom| vent |/ door to: Kitchen

- - - = hallway, and the vent is in the hall

If you close the 2 doors, it's as if there is a complete wall separating the 2 sides of the house. The vent is on the side with the bedrooms. My roommate practically lives in the living room and I live in my bedroom. He likes all the doors and windows open when he's out there. He's telling me that I should close the 2 doors and then the bedroom side of the house will be just fine. He's wrong, but how do you prove that to someone who is ignorant? I found someone saying "a properly installed air conditioning system will be balanced so that sufficient cold air is delivered to and returned from each room of your house." If this is true, that means that even though the return vent is on my side of the house, the other smaller vents are still getting some return in them. Thus, my side of the house will heat up even if those 2 doors are closed. Please, will someone help me get this idiot to close the doors. I'm only asking 11am-noon to 5-6pm that the doors be closed, that's 1/4 of the day (the hottest time of day). Is that really asking too much.

geo fan 07-06-2008 08:50 PM

Settle Down
First off return and supply are different second If the air outside is warmer then the air inside it will obvously impead the capacity and eff. of the system. The counter to that point is if the outside air is cooler then it improves the eff. of the system there are things called ecnomizers designed to do just that take return from the outdoors when its the cooler or less humid of the 2. Here is how you prove your point take temp readings . on a normal day when he has the windows open take a temp reading at the vent in your room then close the doors and windows let the system run for a few mineuts 15 or so and take another temp.

He's probubly doing it to piss you off sounds like your the type to have fun with , but being a conservationist , if all else fails zoneing , adding returns or moving will all help

jammer99 07-07-2008 09:55 AM

You only have one vent?
There must not be any exposure to the outside around this vent.

I would probably buy a portable AC for your room and turn off the central AC.

Taylor Crockett 07-07-2008 05:04 PM

THANK YOU!!! That has helped a great deal. At least I have some arsenal now. Wish me luck. Ignorance is hard to defeat.

geo fan: That makes sense now. Supply vents supply the new, cold air. I'm sorry about looking foolish.

jammer99: I have one return vent and 6 supple vents. Sorry to be confusing.

Thanks again,


By the way, if anyone wants a good laugh, he actually believes A/C makes you weaker.

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