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Efficient use of Air conditioner
Can not convince wife about two things. Just want to bring it here for
a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom |
#2
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Efficient use of Air conditioner
"tom" wrote in message om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom 1 - this depends upon the temperature Vs time profile, A and B are good strategies with certain profiles. you also need the humidity levels/profile, as air that is cooler but has a lot of moister causes the AC to run longer to remove the water. If you have 30% humidity, widows open, 80%, windows closed. Look up latent heat. 2.- Method A. Get that superheated air out (140F) and start with 80F |
#3
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Efficient use of Air conditioner
micheal wrote:
"tom" wrote in message 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? 2.- Method A. Get that superheated air out (140F) and start with 80F Modified method A: Start the AC at the same time as you open the windows. The system will take a few moments to start producing cool air, so you might as well have it do the pre-cooling in parallel. Won't make much difference to the energy cost, and the total time to a cool car will be less. After you've closed the windows, set the AC to recirculate for a while until the car has reached a comfortable temperature. Some climate control systems do this automatically. |
#4
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Efficient use of Air conditioner
"tom" wrote in message
om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom Method A is probably going to be moer efficient in both cases. So what? The energy and money you save doing it your way would not offset the cost of a divorce. Do it your wife's way whenever she's around. |
#5
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Efficient use of Air conditioner
tom wrote in message
om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? If there is no wind (or no fan blowing the cool air into your house), then neither method A nor method B will cool the house down more quickly. This is because the air return to the AC system is inside the house. The hot air will not get 'blown out' of the house. And there will be minimal air exchange through the windows. As the wind increases, eventually method A will cool the house down more quickly. However, it will take a good sized wind or big windows to beat the AC. AC units typically cool the air about 20 degrees F. So the air coming out of the AC will be at 61 F (starting with 81 F), regardless of where the thermostat is set. (Let your wife win on this one.) If you want to save electricity, buy a window fan. 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Method A here will cool the air inside the car faster. But the main source of heat in the car is not the air, but the roof, seats, floor, windows and dashboard. They've all been heated to uncomfortable levels, and the heat capacity of the air is minimal, compared to the rest. Once the air has been blown out (which will take about 2 seconds), you can safely close the windows. There is no electricity in a car AC system (except in an electric car)... the AC compressor runs off of an engine belt. -- greywolf42 ubi dubium ibi libertas {remove planet for return e-mail} |
#6
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Efficient use of Air conditioner
"DHatheway" wrote in message ... "tom" wrote in message om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom Method A is probably going to be moer efficient in both cases. So what? The energy and money you save doing it your way would not offset the cost of a divorce. Do it your wife's way whenever she's around. So true! Don't waste your time and energy on this trivial crap. Brigitte |
#7
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Efficient use of Air conditioner
tom wrote:
Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? There are far too many variables to say one or the other. I will say the one thing many people miss when they try to figure this out is the very high cost of removing the moisture that comes in from outside. However I do have an answer. Real time test! Try it both ways several times. See what works best (more comfortable and less run time) Repeat several times on different days. Keep records and let us know the answer. (Local weather may provide degree days so you can adjust for different outside temps to some degree. 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Most cars burn gas not electricity. ;-) Generally I would guess opening the windows for the first quarter mile to exchange the hot inside air, then shutting it up. There have been a number of test that indicate that cars with A/C get better mileage using the A/C than by opening the windows because of all the wind resistance added by the open windows. Thanks! -Tom -- Joseph E. Meehan 26 + 6 = 1 It's Irish Math |
#8
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Efficient use of Air conditioner
Joseph Meehan wrote
...the very high cost of removing the moisture that comes in from outside. That's a low cost, unless water vapor condenses inside the house. Nick |
#9
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Efficient use of Air conditioner
"DHatheway" wrote in message ... "tom" wrote in message om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom Method A is probably going to be moer efficient in both cases. So what? The energy and money you save doing it your way would not offset the cost of a divorce. Do it your wife's way whenever she's around. It also has to do with air filtration. |
#10
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Efficient use of Air conditioner
"tom" wrote in message
om... Can not convince wife about two things. Just want to bring it here for a serious judgement: You must be young. You will soon learn that with regard to climate control, women are completely out of their minds. There's simply no point in arguing. If she wants to waste money doing the wrong thing, let her. In my wing of my office building, there are 3 small offices, one of which is mine. Three separate tenants, in other words. The thermostat is in the office next door. Three women work in that office, ranging in age from 30 to 60. At almost any time of year, I couldn't figure out how to dress comfortably because of the huge temperature swings. It got to the point where I brought in a recording thermometer that I use around the garden. In any 8 hour day, the temp would vary as much as 20 degrees. The ladies thought this was funny. Finally, the landlord put a locked box over the thermostat and set it for 72. The ladies swore the temp was all over the place, so the landlord brought in a digital recording thermometer. (Big office park, well equipped). It showed a temp range of about 2 degrees either side of 72. End of problem. Just give up. |
#11
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Efficient use of Air conditioner
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#12
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Efficient use of Air conditioner
This is Turtle.
Reply split in parts "tom" wrote in message om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? What Price do you set on your Happiness ? That will be the Price you'll pay for having it your way or not choosing Method B. 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? What Price do you set on having a enjoyful Drive everywhere you may go ? That will be the price you will pay for not choosing Method B. Thanks! -Tom Now you have a choice here by Choosing Method B and have a enjoyful life or Choosing Method A and Paying the Ultimate Price on Happiness the rest of your life. I even think your going to pay the Ultima price even asking this question. TURTLE --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.714 / Virus Database: 470 - Release Date: 7/2/2004 |
#13
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Efficient use of Air conditioner
"HeatMan" wrote in message nk.net... "DHatheway" wrote in message ... "tom" wrote in message om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom Method A is probably going to be moer efficient in both cases. So what? The energy and money you save doing it your way would not offset the cost of a divorce. Do it your wife's way whenever she's around. It also has to do with air filtration. This is Turtle. Would that filter be for the **** coming his way also ? TURTLE --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.714 / Virus Database: 470 - Release Date: 7/2/2004 |
#14
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Efficient use of Air conditioner
"tom" wrote in message om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? PROBABLY B. What you say? Simple..opening the windows will remove some of the warm air, but unless you have a whole house fan pulling like hell, you wont be able to use all that cool air out, and you still have latent heat in the walls, floors, ceiling...furniture...etc.. But my queston is....why are you allowing your air in the home to reach 81F? Set your thermostat and forget it...its cheaper that way.. 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Again...depends. Personally, my personal work van for example, has these neat little vents in the taillights...fire the AC up, open they go, and out goes the hot air.... And even when I was in CA,I didnt worry about that stuff...I just went on with it... Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom |
#16
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Efficient use of Air conditioner
CBHVAC wrote:
"tom" wrote: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? PROBABLY B. What you say? Simple..opening the windows will remove some of the warm air, but unless you have a whole house fan pulling like hell, you wont be able to use all that cool air out, and you still have latent heat in the walls, floors, ceiling...furniture...etc.. Why latent heat, ie condensation? But my queston is....why are you allowing your air in the home to reach 81F? Set your thermostat and forget it...its cheaper that way.. Newton was wrong? :-) Nick |
#17
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#18
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Efficient use of Air conditioner
Guys, Thanks a million for your answers and advices! It's nothing
about how to save more money. I just meant to remind my wife "hey, I'm not that stupid, you forgot?" This is kind of once-a-year event. Last time we argued about the pronunciation of a word. It was 16 months ago and loser would be slapped (she proposed that) After we looked it up in our dictionary, she ran away quickly. |
#19
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Efficient use of Air conditioner
wrote
...the very high cost of removing the moisture that comes in from outside. That's a low cost, unless water vapor condenses inside the house. And just why do you think air conditioners have drip pans? To remove liquid water from walls and furniture? :-) Nick |
#20
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Efficient use of Air conditioner
"tom" wrote in message om... Guys, Thanks a million for your answers and advices! It's nothing about how to save more money. I just meant to remind my wife "hey, I'm not that stupid, you forgot?" This is kind of once-a-year event. Last time we argued about the pronunciation of a word. It was 16 months ago and loser would be slapped (she proposed that) After we looked it up in our dictionary, she ran away quickly. The loser would be slapped? Unless she meant you could spank her, you better get the hell out of there quick, buddy. Next thing you know, she'll be proposing dueling with hatchets. |
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#22
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#23
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Efficient use of Air conditioner
John Barry wrote:
wrote in message ... Joseph Meehan wrote ...the very high cost of removing the moisture that comes in from outside. That's a low cost, unless water vapor condenses inside the house. Nick Maybe not. What Joe's pointing to, I'll bet, is the latent heat of condensation that must be dealt with in the a/c evaporator, on condensing the moisture there. For a given mass of water, that's about half the latent heat of boiling the water. How is that again?????? A new law of physics? Almost certainly a significant energy expense, never mind that high humidity indoors is "yucky" (TM) until the water vapor is reduced. Were you considering only water-damage to house contents other than a/c air-movers? I'd be slower to dismiss. john -- Joseph E. Meehan 26 + 6 = 1 It's Irish Math |
#24
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Efficient use of Air conditioner
On 20 Jul 2004 07:28:37 -0700, someone wrote:
-Tom So what will you do with our answers? Do you think you would really accomplish anything showing them to her? Does what anonymous strangers say "prove" anything? Do you really think you can "win" an argument with your spouse? -v. |
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Efficient use of Air conditioner
"v" wrote in message ... On 20 Jul 2004 07:28:37 -0700, someone wrote: -Tom So what will you do with our answers? Do you think you would really accomplish anything showing them to her? Does what anonymous strangers say "prove" anything? Do you really think you can "win" an argument with your spouse? -v. Actually, all these answers might help, but for a sick reason. Some people insist on seeing things in writing, and they're satisfied even if the writers are rank amateurs. My ex was that way. Couldn't trust her own observations. |
#26
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Efficient use of Air conditioner
wrote in message The best use of a house A/C is to use it with a fan. Nobody believes me when I say that I cool my house with a 5000 BTU A/C and two fans. Add me to the list. Unless you have a very small house and moderate climate, that small of a unit will do very little. I agree a fan can help immensely with air circulation, you still need a certain amount of capacity to move a given heat load. If you have a two room cabin, OK, if you have a 2,000 sq. ft. Colonial, you are full of BS. |
#27
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#28
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Efficient use of Air conditioner
In article ,
"Edwin Pawlowski" wrote: wrote in message The best use of a house A/C is to use it with a fan. Nobody believes me when I say that I cool my house with a 5000 BTU A/C and two fans. Add me to the list. Ah, well. :-) .. Unless you have a very small house and moderate climate, that small of a unit will do very little. I think most people would consider the house small. However, I also know about arranging tree shade, insulation, and do not need the house to be 65 degrees for comfort. 65 is too cold. If I can get the house cooled down below 70 at night, I don't need the A/C to be on at all. I simply shut the windows to keep the heat out and run a fan for circulation. The house doesn't get hot until ~17:00. By then it's usually cool enough outside to cool the house. ...I agree a fan can help immensely with air circulation, you still need a certain amount of capacity to move a given heat load. Nah. All you have to do is move the hot air into the room that has the A/C. Voila! Cool house. It helps for that room to have two doors going into two rooms that eventually connect with each other. The rooms aren't configured like spokes in a wheel without a rim. If you have a two room cabin, OK, if you have a 2,000 sq. ft. Colonial, you are full of BS. The only thing you have to do is cool the one room, then move the cooled air out and the warmer air in. /BAH Subtract a hundred and four for e-mail. |
#29
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Efficient use of Air conditioner
wrote in message ... In article , "Edwin Pawlowski" wrote: wrote in message The best use of a house A/C is to use it with a fan. Nobody believes me when I say that I cool my house with a 5000 BTU A/C and two fans. Add me to the list. Ah, well. :-) .. Unless you have a very small house and moderate climate, that small of a unit will do very little. I think most people would consider the house small. However, I also know about arranging tree shade, insulation, and do not need the house to be 65 degrees for comfort. 65 is too cold. If I can get the house cooled down below 70 at night, I don't need the A/C to be on at all. I simply shut the windows to keep the heat out and run a fan for circulation. The house doesn't get hot until ~17:00. By then it's usually cool enough outside to cool the house. How do I "arrange tree shade"? Trees in big planters on wheels? ...I agree a fan can help immensely with air circulation, you still need a certain amount of capacity to move a given heat load. Nah. All you have to do is move the hot air into the room that has the A/C. Voila! Cool house. It helps for that room to have two doors going into two rooms that eventually connect with each other. The rooms aren't configured like spokes in a wheel without a rim. If you have a two room cabin, OK, if you have a 2,000 sq. ft. Colonial, you are full of BS. The only thing you have to do is cool the one room, then move the cooled air out and the warmer air in. In San Diego, it has been pretty hot, but not too humid, the last few days. We have survived without A/C by running oscillating fans indoors and seeking shade/breeze locations outdoors (except for my retaining-wall project, which is on an unshaded south-facing hill). Upstairs we keep a fan in the south-facing window and a ceiling fan running all the time in the master bedroom. My son's room faces east - a window fan turned on after dark makes that room comparitively frigid. If things get really bad, we drive down to the grocery store and stand in front of the meat cooler. |
#30
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Efficient use of Air conditioner
In article 5TMLc.28901$9I.20458@okepread02,
"Richard Henry" wrote: wrote in message ... snip .. Unless you have a very small house and moderate climate, that small of a unit will do very little. I think most people would consider the house small. However, I also know about arranging tree shade, insulation, and do not need the house to be 65 degrees for comfort. 65 is too cold. If I can get the house cooled down below 70 at night, I don't need the A/C to be on at all. I simply shut the windows to keep the heat out and run a fan for circulation. The house doesn't get hot until ~17:00. By then it's usually cool enough outside to cool the house. How do I "arrange tree shade"? Trees in big planters on wheels? You can. Awnings or shutters help. Shutters are neat in that you can shut out the sunlight and keep the airflow going. Curtains block air flow. I'd have to see the layout of your yard and house to tell if growing stuff would help. snip The only thing you have to do is cool the one room, then move the cooled air out and the warmer air in. In San Diego, it has been pretty hot, but not too humid, the last few days. We have survived without A/C by running oscillating fans indoors and seeking shade/breeze locations outdoors (except for my retaining-wall project, which is on an unshaded south-facing hill). That wall will absorb and the emit heat. A good thing in winter, but not desired in summer. Shading it with plants that deleaf in the winter is one way to arrange shade. ...Upstairs we keep a fan in the south-facing window and a ceiling fan running all the time in the master bedroom. My son's room faces east - a window fan turned on after dark makes that room comparitively frigid. I cool the house down by placing a fan facing out and running it. If you have an attic fan, then you want to place the first floor fans facing in but only run them that way when it's cooler outside than inside. During the heat of the day, shut the windows or leave a couple strategically placed windows open a crack for oxygen. Then run fans that circulate the air inside only, in a down to up direction. If things get really bad, we drive down to the grocery store and stand in front of the meat cooler. I put on my winter woolies before I walk in the grocery store. It's ****ing freezing in those stores...but not as cold as the post office. There is no mystery about why those people go postal; their brains get frozen to the point of no possible electrical activity. I want to put on a wool face mask when I walk into those buildings. /BAH Subtract a hundred and four for e-mail. |
#31
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wrote:
Joseph Meehan wrote ...the very high cost of removing the moisture that comes in from outside. That's a low cost, unless water vapor condenses inside the house. We were talking about a) ventilating a house at night vs b) keeping an AC running. I'm thinking a) is better, as long as we don't have condensation inside the house. Take a given volume of air at 90 F and 40%. Why 90 F and 40%? How much energy does it take to cool the air to say 72 F? Depends on the volume :-) How much energy does it take to cool and condense enough water to get down to 40% at 72 F? Why 40%? Standard ASHRAE humans are comfy at 56% and 80.2 F. ...Without running through the math, I would think getting the water vapor out is the energy expensive part. Try math! If your 32x32x8' house has 6K Btu/F of fast capacitance and 400 Btu/h-F of thermal conductance, including 200 cfm of air leaks, and it's 78% and 71 F in the morning, and the outdoor temp hits 92 in the afternoon, with the morning humidity ratio, which is better, a) or b)? Nick |
#32
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Efficient use of Air conditioner
Turn on a/c in house and leave it on.
Tom "tom" wrote in message om... Can not convince wife about two things. Just want to bring it here for a serious judgement: 1. Use Air conditioner for home at night: Temperature outside = 69F, Temp in home = 81F, Air conditioner trigger set to 75F method A. With windows being open - My way method B. With windows being closed - Wife's way Question: which one make house temp drop faster and which one costs less electricity? 2. Use AC for car in a hot summer day Temperature outside = 80F, Temp of a car parked in sun for one hour = very hot, don't know exact temp After getting into the car Method A: open windows, drive for a moment then close the windows and start AC. - mine Method B: Start AC right away without opening windows. - wife's Question: which one make car temp drop faster and which one costs less electricity? Thanks! -Tom |
#33
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#36
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Efficient use of Air conditioner
wrote in message ... wrote: Joseph Meehan wrote ...the very high cost of removing the moisture that comes in from outside. That's a low cost, unless water vapor condenses inside the house. We were talking about a) ventilating a house at night vs b) keeping an AC running. I'm thinking a) is better, as long as we don't have condensation inside the house. Take a given volume of air at 90 F and 40%. Why 90 F and 40%? How much energy does it take to cool the air to say 72 F? Depends on the volume :-) How much energy does it take to cool and condense enough water to get down to 40% at 72 F? Why 40%? Standard ASHRAE humans are comfy at 56% and 80.2 F. ...Without running through the math, I would think getting the water vapor out is the energy expensive part. Try math! If your 32x32x8' house has 6K Btu/F of fast capacitance and 400 Btu/h-F of thermal conductance, including 200 cfm of air leaks, and it's 78% and 71 F in the morning, and the outdoor temp hits 92 in the afternoon, with the morning humidity ratio, which is better, a) or b)? If you walk out on your back porch and don't have enough pancakes to build a fence True or False? False because bicycles don't have hotdogs with flat sidewalks. |
#37
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Efficient use of Air conditioner
wrote in message ... In article , "Edwin Pawlowski" wrote: wrote in message The best use of a house A/C is to use it with a fan. Nobody believes me when I say that I cool my house with a 5000 BTU A/C and two fans. Add me to the list. Ah, well. :-) .. Unless you have a very small house and moderate climate, that small of a unit will do very little. I think most people would consider the house small. However, I also know about arranging tree shade, insulation, and do not need the house to be 65 degrees for comfort. 65 is too cold. If I can get the house cooled down below 70 at night, I don't need the A/C to be on at all. I simply shut the windows to keep the heat out and run a fan for circulation. The house doesn't get hot until ~17:00. By then it's usually cool enough outside to cool the house. Shutting the windows only works if no direct sunlight never hits the windows. If it does, the temperature will increase faster inside the house than it would with the windows open, especially if the floors are concrete. It also depends on the thermal mass of your insulation. The higher the thermal mass, the slower the walls are to change temperature. This is usually a good thing where temperatures change above and below a desirable temperature from day to night. It causes the temperature to somewhat regulate inside. That's why underground is at a relatively constant temperature. ...I agree a fan can help immensely with air circulation, you still need a certain amount of capacity to move a given heat load. Nah. All you have to do is move the hot air into the room that has the A/C. Voila! Cool house. It helps for that room to have two doors going into two rooms that eventually connect with each other. The rooms aren't configured like spokes in a wheel without a rim. If you have a two room cabin, OK, if you have a 2,000 sq. ft. Colonial, you are full of BS. The only thing you have to do is cool the one room, then move the cooled air out and the warmer air in. /BAH Subtract a hundred and four for e-mail. |
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Efficient use of Air conditioner
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Efficient use of Air conditioner
On Thu, 22 Jul 2004 13:06:54 -0600, "Timm Simpkins"
wrote: wrote in message If you walk out on your back porch and don't have enough pancakes to build a fence True or False? False because bicycles don't have hotdogs with flat sidewalks. Nick's does - he built it himself. Damned thing won't roll, but it's very efficient...... Paul ( pjm @ pobox . com ) - remove spaces to email me 'Some days, it's just not worth chewing through the restraints.' HVAC/R program for Palm PDA's Free demo now available online http://pmilligan.net/palm/ Free Temperature / Pressure charts for 38 Ref's http://pmilligan.net/pmtherm/ |
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Efficient use of Air conditioner
writes:
In article , writes: Joseph Meehan wrote ...the very high cost of removing the moisture that comes in from outside. That's a low cost, unless water vapor condenses inside the house. And just why do you think air conditioners have drip pans? Speaking of which, there is some potential cooling assist in the condensate. The condensate will be about the temp. of the evaporator when it's formed, that is, rather cool. There is cooling ability both in warming this water, and in re-evaporating it. Let's say you either use this water to cool the freon going into the condensor coil or that leaving the condensor. Which is more efficient (in amount of cooling per kWh)? The freon going into the condensor is hot, so maybe the water will re-evaporate, taking with it more heat. Or the condensate cools the freon leaving the condensor coil, cooling it even further, meaning the freon entering the evaporator coil will be cooler, meaning the A/C output is cooler, but it is less likely to evaporate. (Both the warmed condensate and evaporated condensate are dumped outside) Any thoughts? -- -Mike |
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