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

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Taylor Crockett
07-06-08, 04:30 PM
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.

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

- - - = 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.


Gunguy45
07-06-08, 04:53 PM
Well, yes first of all your roomate isn't too smart. Also, there is no insulation in the interior walls or doors, so any heat just migrates right through. Common areas are common areas, let him close HIS bedroom door and open all HIS windows.

If you can keep your area cool, just let him pay 2/3 of bill. Appeal to his green side, the A/C is working harder and will need to be replaced sooner, depleting the Earth of badly needed elements. It's also increasing global warming by all that excess heat being emitted from your unit.


Or just kick his butt out, or move yourself...prob easier.

ecman51`
07-07-08, 03:53 PM
But even with the doors closed, you can barely feel the A/C during the day. I live in Pasadena (Los Angeles), CA.



You can barely feel that the house is cooling? Or, more telling - can you tell us what the temp is that is coming out say the closest register to the cooling coils (the one closest to your attic's handling unit), and what kind of temp is at a cold air return. Usually a/c units like yours can only put out like 16 degrees or so colder than what the air coming back into the furnaces cold air return is. Like, if your house is say 78 degrees inside and you then turn on the a/c, you might expect the a/c at a register to say 62 degrees. (Or if the house is 75, it should put out about 59. Etc.). These aren't exact numbers, but you get the idea.

Let us know what your numbers are.


Taylor Crockett
07-07-08, 04:04 PM
THANK YOU!!! That has helped a great deal. At least I have some arsenal now. Wish me luck. Ignorance is hard to defeat.

Thanks again,
Taylor


p.s. - I'M BURNING UP HERE!!!



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

ecman51`
07-07-08, 04:23 PM
Anxious to hear numbers from you.

Regarding your last comment: It sounds silly, but one really never knows, when considering every aspect of what is involved when one relies on artificial cooling. Ask him what he means by that exactly. Does he mean weaker as in no longer being a he-man, capable of tolerating the various hardhips in life? Or does he mean that it like tires you and you feel like you have to crash out on the couch when the a/c is on?