Heat Goes in or Cold Goes Out? Why Air-conditioned Rooms Should be Kept Closed
We have become fully detached from the scientific field and our relative ignorance of it is certainly not ridiculous. However, it is likewise a delight if we ourselves can explain in a scientific manner some things that we are doing everyday. One instance of it is the norm of keeping air-conditioned rooms closed.
Opening and closing air conditioned rooms is one of life’s activities of many people around the world. Because of the fact that not everyone has the affinity for science, augmented by one’s natural tendency to hold on self-conceptualized ideas, we are at times left believing in uncertain conceptions. Our keeping air-conditioned rooms closed most likely hinged not on fear of a theft or anything for that matter; it is to prevent the room from getting hot. Surely, it’s not much of a deal, but knowing even the slightest truth can always be a pleasure to our naturally inquisitive mind. We all have the passion to know even the smallest of things, only that our enslaving days work deprives us of such pleasures.
Knowing the exact ground of keeping air conditioned rooms closed is one of such small things. Contrary to the belief of some, air-conditioned rooms are kept closed in order to prevent heat energy from coming in, not the cold from coming out. This fact is grounded on a natural law, otherwise known as the 2nd law of thermodynamics in classical physics. It presents the fact of heat being naturally constrained to flow from a high temperature to low temperature region. In a similar situation to an air-conditioned room, it is a region of low temperature and outside of it is region of high temperature. So, the 2nd law of thermodynamics entails that once the room is opened, a speedy inflow of heat from the outside will ensue.
The natural flow of heat from a warmer surrounding to a cooler surrounding is naturally irreversible. It can be reversed only at the expense of doing work on the system. This is how air-conditioned rooms work, heat inside the room is continuously being pick up by the air-conditioner and is thrown to the relatively warmer surrounding outside; it’s a flow of heat from low to high temperature but is surely not a violation of the 2nd law of thermodynamics due to the work being done on the system by the machine. Air conditioner is the machine that reverses the natural flow of heat. It makes heat flow from low to high temperature.
Air conditioned rooms should therefore be kept closed; otherwise the natural tendency of heat to flow from high to low temperature – will easily overwhelm the reversing ability of air conditioners, instantly heating up the room. Further, the introduction of heat will quickly increase the work load of the machine, thus an immediate increase in electrical energy consumption.
Liked it
25 Responses to “Heat Goes in or Cold Goes Out? Why Air-conditioned Rooms Should be Kept Closed”
On March 9, 2009 at 10:59 am
a refresher of my barely passing grade regarding enthropy.. why am I shuddering?.. great share, really applicable to daily living..
On March 9, 2009 at 12:13 pm
Thanks for explaining something that I knew about but didn’t understand the whys and wherefores of it.
On March 9, 2009 at 12:38 pm
another lesson in Thermo Dynamics. Thanks for sharing.
On March 9, 2009 at 2:02 pm
Thanks for making this clear, Unofre. My bedroom is in a loft area so unfortunately there are no doors to close. I do have an air conditioner up there but it really isn’t effective until the sun goes down.
On March 9, 2009 at 2:12 pm
You learn something new every day. I had no idea about how thermo dynamics works. Thank you for explaining it so well.
Christine
On March 9, 2009 at 3:18 pm
A dinamic thermo dinamic explanation .
On March 9, 2009 at 4:01 pm
Awesome and very interesting article.
On March 9, 2009 at 4:32 pm
Sa physics, tameme ako. Huwag kang magtanong dahil di ko alam, tanong mo kay Unofre dahil magaling siya diyan.
On March 9, 2009 at 5:10 pm
I loved my college thermo class! Fun stuff. Nice writeup here.
On March 9, 2009 at 6:43 pm
I get irriated when I go inside a store that has the air or heat running and the entrance is wide open. It makes me wonder where their head is. Don’t they know its money running the door?
On March 9, 2009 at 10:00 pm
Really thought provoking piece Unofre. Thanks.
RJ
On March 9, 2009 at 10:55 pm
nice scientific explanation bro,thanks
On March 10, 2009 at 3:09 am
You never cease to impress me with your scientific know-how! Great article as usual
On March 10, 2009 at 6:20 am
I don’t see why this is such a problem for people to understand. It seems totally clear to me.
On the flip side, if you live in a country where it’s perpetually cold, you learn this from a very young age. An open door leaves a room feeling very cold indeed.
On March 10, 2009 at 9:27 am
informative
On March 10, 2009 at 3:58 pm
Very well written piece..you have honestly made an effort…
On March 10, 2009 at 5:53 pm
Excellent! That was great. Nicely done and very well explanation abt AC dinamic thermo/ theory. Thanks for sharing
On March 11, 2009 at 2:43 am
Well done my friend. Now I know how it works!
On March 11, 2009 at 7:21 am
It’s good to know about the theory. Well done.
On March 11, 2009 at 8:30 am
A thermo dynamics special course from Unofre. Well presented my friend! If I am your teacher I will give an A grade…
On March 11, 2009 at 10:55 pm
Very useful tips, thanks
On March 12, 2009 at 5:25 pm
Great article well written.
On March 21, 2009 at 9:44 pm
I’m an Engineer… But, a computer one. However, this item was discussed in Physics and other major subjects I’ve taken in College. Great choice of topic.
On March 21, 2009 at 10:11 pm
Wow, I have been flown back to my physics days in MSU, thanks. Kabs.
On June 5, 2009 at 5:05 am
Great article. Miss your exceptional articles. My work leaves me very little to surf the net, let alone write.
Post Comment