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Freezing pipes ************************************************** *****
Hello Everybody,
Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? |
Rettgerinc wrote:
Hello Everybody, Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? If there are significant periods of time when water is not flowing through the hot pipes, i.e. no "hot" faucets are opened and the system does not use a circulating pump or a thermosyphon loop to provide "quicker hot water", then there will be no difference in the freezing time. Jeff -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) "As long as there are final exams, there will be prayer in public schools" |
Hello Everybody, Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? Hmm...I don't know what the scientific answer is going to be but last year we had a burst and *both* the hot *and* cold pipes split in almost the same places (they were side by side). These pipes ran along an outside wall and ran to the washer hook-up. We had only been living in the house for 2 weeks when they burst and I didn't know where the shut off valve was. Water was jetting up from the splits, hitting the roof and coming down again like a waterfall! At first I thought it was the upstairs neighbour who had the leak until I plunged under the waterfall to discover the splits in both pipes. I found the hot water shut off close to the hot water tank but the cold water eluded me for a while and finally I had to call the landlord and ask him where it was. It turned out to be located under a false 'floor' in the bathroom 'cupboard'! By the time I got the cold water shut off we had 2-3" of water on the floor. So from my experience they can both go at the same time...lol. -- Larry Green |
http://math.ucr.edu/home/baez/physic...hot_water.html
"Rettgerinc" wrote in message ... Hello Everybody, Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? |
"Larry Green" wrote: (clip) the cold water eluded me for a while and finally I had to call the landlord and ask him where it was. (clip) ^^^^^^^^^^^^^ And did the landlord take care of the repair, or were you stuck for it. |
"Larry Green" wrote: (clip) the cold water eluded me for a while and finally I had to call the landlord and ask him where it was. (clip) ^^^^^^^^^^^^^ And did the landlord take care of the repair, or were you stuck for it. He was there within 5-10 minutes of my call along with his wife and both are retirement age. He made the repairs *after* he and his wife helped 'bail out' the utility room using buckets, mops and snow shovels! Thankfully the floor in there is about 3" lower than the rest of the house so most of the water was contained to the floor of the one room. My biggest concern was the 'waterfall' of water was spraying all over the rather old electrical panels located directly above the breaks but once the leak was stopped I checked the panels and they were bone dry......PHEW! It turns out the exhaust duct for the dryer only had a plastic shopping bag stuffed in it and an icy wind had been 'funnelled' directly over the pipes freezing them solid and splitting the copper pipes. Obviously the water then burst through when they thawed. As we did not have a machine hooked up at the time we never noticed they were frozen in the first place. -- Larry Green |
Pipes don't freeze. It's the water in them that does. If the water in both
pipes becomes stagnant then it will freeze if pipe temperature falls significantly below freezing long enough. As to which water in which pipe will freeze first and you're into splitting hairs, then I guess if the last usage pattern was identical (both hot and cold water used simultaneously at same pressure levels) then theoretically the water in the cold water pipe should freeze first since it was originally at a lower temperature. I'm not a plumber so something could be missing in my reply. What I do know is that allowing just a trickle of water to flow in either pipe will prevent freezing and many less fortunate take advantage of this since water bills are lower than heating (gas, oil or electricity) bills. "Rettgerinc" wrote in message ... Hello Everybody, Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? |
Yup.
The hot water heater reduces the dissolved minerals slightly, mainly carbonates; enough to make a slight difference in the freezing point. Bugs |
I think that article gives an explanation as to why if ever the "hot water"
freezes faster. Yes, it's news to me but it's not categorically stating that water in the "hot" pipes will always freeze faster. "Bugs" wrote in message ups.com... Yup. The hot water heater reduces the dissolved minerals slightly, mainly carbonates; enough to make a slight difference in the freezing point. Bugs |
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Ah, the old canard about hot water freezing before the cold water will!
Here's how the canard got started. If you take some hot water and cold water and put them into the freezer, the hot water will lose heat faster than the cold water will. This is indeed true as the hot water has a lot higher temp differential than the colder water will. As a result of this heat loss, the typical idiot will conclude that the hot will freeze before the cold water will because it will be losing heat faster than the cold water will. The reason he's an idiot is that the hot water when it gets colder, will lose heat at the same rate that the cold water was losing it. As a result, the hot water will always be behind the cold water in getting to the freezing point. The curve of heat loss isn't a linear slope but rather a curved slope depending upon the instantenous temp differential between the water and the air surrounding it. I'll note that when playing this game in the freezer, you can make it turn out differently depending upon how much of the glass is touching the cold stuff inside and which glass it is. Touching some cold meat or such will increase the transfer of heat out of the glass and that will drastically affect the actual point at which the freezing begins. -- Why isn't there an Ozone Hole at the NORTH Pole? |
"Bob May" wrote: (clip) As a result of this heat loss, the typical idiot will conclude that the hot will freeze before the cold water will because it will be losing heat faster than the cold water will. (clip) ^^^^^^^^^^^^^^^^ But how would an idiot know how fast the water is losing heat? I suppose the same idiot will conclude that a car will coast farther from 30 MPH than from 60 MPH. I met that guy once. He was low on gas, so he drove really fast, so he would get home before he ran out. G |
On Sat, 25 Dec 2004 22:45:24 GMT, "Leo Lichtman"
wrote: "Bob May" wrote: (clip) As a result of this heat loss, the typical idiot will conclude that the hot will freeze before the cold water will because it will be losing heat faster than the cold water will. (clip) ^^^^^^^^^^^^^^^^ But how would an idiot know how fast the water is losing heat? I suppose the same idiot will conclude that a car will coast farther from 30 MPH than from 60 MPH. I met that guy once. He was low on gas, so he drove really fast, so he would get home before he ran out. G I knew a milk driver that did that because his brakes were bad and he had to hurry home to fix them... Garry PS I have heard of hot water freezing so fast the ice was still hot... |
In article i9kzd.5978$1U6.1462@trnddc09, says...
"Ned Simmons" wrote in message ... In article 5Hhzd.6464$h.4018@trnddc04, says... I half filled two identical drinking glasses with water.and placed them in the freezer. one glass had 60 degree water and the other had 80 degree water. It took a little over an hour for the "cold tap filled" glass to form crystals while the "warm water filled" was still without crystals. The odd part was that both waters were at the same temperature after 1 hour and 15 minutes, yet the cold water filled was much more crystalized. Go figure!! Toying with us again, Jerry, or just trolling? g Ned I must have been obscure with my explanation about testing the theory that "hot water" will freeze more quickly than "cold water". I assume the theory is correct, but only under special-limited conditions. Tell me what I made obscure, or 'trolllike'. Jerry I got the feeling you were being coy about the reason the two glasses were stuck at the same temperature -- the large heat of fusion of water. Was I mistaken? Ned Simmons |
"Ned Simmons" wrote in message ... In article i9kzd.5978$1U6.1462@trnddc09, says... "Ned Simmons" wrote in message ... In article 5Hhzd.6464$h.4018@trnddc04, says... I half filled two identical drinking glasses with water.and placed them in the freezer. one glass had 60 degree water and the other had 80 degree water. It took a little over an hour for the "cold tap filled" glass to form crystals while the "warm water filled" was still without crystals. The odd part was that both waters were at the same temperature after 1 hour and 15 minutes, yet the cold water filled was much more crystalized. Go figure!! Toying with us again, Jerry, or just trolling? g Ned I must have been obscure with my explanation about testing the theory that "hot water" will freeze more quickly than "cold water". I assume the theory is correct, but only under special-limited conditions. Tell me what I made obscure, or 'trolllike'. Jerry I got the feeling you were being coy about the reason the two glasses were stuck at the same temperature -- the large heat of fusion of water. Was I mistaken? Ned I was real doubtfull that warm water from the hot water tap would freeze before cooler water taken from the cold water tap, so I tested it. I began the test with one glass at 60 degrees and the other at 80 degrees. It took about an hour and a quarter for the 1/2 full 'glass of water' began to develop crystals. Both glasses were placed close together and in the same environment. I measured the water temperature at about every 15 minutes. As you'd expect, the water from the warm water tap was always warmer than the water from the cold water tap. But after about an hour the difference between the two temperatures was undetectable with my thermometer. But crystals did form in the glass that had been filled from the cold water tap. I wouldnt br surprized to,learn that there is a chemical difference in the two waters. Something probably boils out of the water in the hot water heater. It actually surprized me that *my* water freezed the water from the cold water tap first. I suspect Bill's water from the warm water tap has had changed in some way thats different from the change in *my* water. I have heard about this "Hot water freezes before cold water" in 1949 when I was in the USAF, in Alaska. I never could accept the validity of that statement. But I do know that there are conditions where the convection currents within the hot water container serve to distribute the temperature. And, it might be that the hot water had some gasses boiled out thereby providing a better condition for freezing. I had always thought the "hot water freezes quicker" was restricted to special labroatory experiments, till Bill said he freezes warm water more quickly than cooler water in his "refrigerator freezer". So, I tried it today. I dont know any more now than when I started. Jerry |
On 25 Dec 2004 06:05:22 GMT, Ignoramus10474
wrote: a hot pipe never freezes. Technically you may be right - but the hot water pipe, when it cools down, most definitely does. And what a mess it makes when it does!!!! The heaters in my brother's shop went out one extremely cold winter weekend. The water pipes, back then, were strapped directly to the concrete block wall (they are now strapped out about 2 inches) and when the pipes froze and split a SMALL amount of water worked it's way down the pipes. The water heater was only a matter of a few feet away - and as soon as SOME water started to move, hot water got to the split and soon there was a spray of VERY hot water shooting in all directions - little more than a geiser of wet steam - which froze in a veil over EVERYTHING. I think it was breaking ice setting off the alarm that caught his attention. i On 25 Dec 2004 02:02:35 GMT, Rettgerinc wrote: Hello Everybody, Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? |
In article 0wrzd.3958$Y57.2782@trnddc08, says...
I have heard about this "Hot water freezes before cold water" in 1949 when I was in the USAF, in Alaska. I never could accept the validity of that statement. But I do know that there are conditions where the convection currents within the hot water container serve to distribute the temperature. And, it might be that the hot water had some gasses boiled out thereby providing a better condition for freezing. Another explanation that seemed to work in my freezer a few years ago. I put a glass of hot water and a glass of cold water on my freezer shelf, and the hot water froze first. When I put the glasses on the plastic bottom shelf, the cold water froze first. If your freezer's cooling coils are built into the shelf, and if you have't defrosted the freezer recently, then the cooling coils will be isulated with a good layer of frost. A glass full of hot water will melt through more of this layer of isulation, so the coil will cool it faster. -- is Joshua Putnam http://www.phred.org/~josh/ Braze your own bicycle frames. See http://www.phred.org/~josh/build/build.html |
I had always thought the "hot water freezes quicker" was restricted to
special labroatory experiments, till Bill said he freezes warm water more quickly than cooler water in his "refrigerator freezer". So, I tried it today. I dont know any more now than when I started. Jerry Jery I found this to happen when I fill my bicycle water bottle with hot water and went on a bicycle ride in sub freezing weather. I assume that the cold air moving over the bottle has an effect. My origianal post is below. As a bicycle riders who has filled my water bottle with water from the hot water tap, I found that the bottle fill with warm water freezes before the bottle filled from the cold water tap. -- www.billcotton.com N40° 3.744' W75° 6.180' |
Interesting link there, kklein! I'm surprised more posters
have not paid more attention to the phenomena of supercooling! That is more interesting to me. I have seen this _many_ times in my sauna, a separate building out back, in the water pails. The temp can go down into the upper twenties and the water in the pails is not frozen but all it takes is the slightest movement and the water crystallizes completely to the bottom! When it's cold I'll check the pails to see if they are ice and if not I'll swirl the bucket with a kauhaa and within minutes it is possible to invert the pail leaving a block of solid ice on the bench! The thing is the water must cool very slowly and in total calm conditions, even vibrations will trigger the freezing. I've been told that even dropping in a single grain of sand is enough to do it but I haven't tried that yet. Phil Kangas N 46 d 53.045' W 88 d 51.717' "kklein" wrote in message http://math.ucr.edu/home/baez/physic...hot_water.html "Rettgerinc" wrote in message Hello Everybody, Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? |
Bill, does that put you on the West side of Rolling Green??
I have thought about that "freezing of water for over 55 years and never took time to test it. Then, when I tried several days ago, I realized how difficult it is to control all parameters in a test like this. I might have been better off if I'd not tried to test the theory. Jerry "Bill Cotton" wrote in message ... I had always thought the "hot water freezes quicker" was restricted to special labroatory experiments, till Bill said he freezes warm water more quickly than cooler water in his "refrigerator freezer". So, I tried it today. I dont know any more now than when I started. Jerry Jery I found this to happen when I fill my bicycle water bottle with hot water and went on a bicycle ride in sub freezing weather. I assume that the cold air moving over the bottle has an effect. My origianal post is below. As a bicycle riders who has filled my water bottle with water from the hot water tap, I found that the bottle fill with warm water freezes before the bottle filled from the cold water tap. -- www.billcotton.com N40° 3.744' W75° 6.180' |
"Jerry Martes" wrote in message news:STLzd.8454$hc7.8310@trnddc06... Bill, does that put you on the West side of Rolling Green?? East side, but the coordinates are from Topo USA, I haven't check with the gps since SA was removed. -- www.billcotton.com N40° 3.744' W75° 6.180' |
Bill I used Street USA. I cant get this computer to accept my Topo USA My lap top accepts both *and* both hook up with the Earthmate GPS. Jerry "Bill Cotton" wrote in message ... "Jerry Martes" wrote in message news:STLzd.8454$hc7.8310@trnddc06... Bill, does that put you on the West side of Rolling Green?? East side, but the coordinates are from Topo USA, I haven't check with the gps since SA was removed. -- www.billcotton.com N40° 3.744' W75° 6.180' |
I don't know about the physics but I was once in the property management
business. When we had a really hard freeze down here the company got several hundred broken pipe calls. 80% of them are on the hot water side. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com "Rettgerinc" wrote in message ... Hello Everybody, Merry Christmas from Pittsburgh, PA It is getting cold here! And I just started a new job with a company that does plumbing, heating, and cooling (I am not the plumber for I studied the heating and cooling and refrigeration) Big question! When the outside temps cause the various inside pipes to freeze and there are both hot and cold pipes that have similar exposure, is the hot pipe going to freeze first? |
There the hot water pipes are more eroded than the cold water ones are as
the heat assists in the corrosion of the pipe material. It ain't that the hot water froze first but rather that the pipes just weren't strong enough to withstand the forces on the pipe from the ice. -- Why isn't there an Ozone Hole at the NORTH Pole? |
In article ,
Bob May wrote: Ah, the old canard about hot water freezing before the cold water will! Here's how the canard got started. If you take some hot water and cold water and put them into the freezer, the hot water will lose heat faster than the cold water will. This is indeed true as the hot water has a lot higher temp differential than the colder water will. As a result of this heat loss, the typical idiot will conclude that the hot will freeze before the cold water will because it will be losing heat faster than the cold water will. The reason he's an idiot is that the hot water when it gets colder, will lose heat at the same rate that the cold water was losing it. As a result, the hot water will always be behind the cold water in getting to the freezing point. The curve of heat loss isn't a linear slope but rather a curved slope depending upon the instantenous temp differential between the water and the air surrounding it. I'll note that when playing this game in the freezer, you can make it turn out differently depending upon how much of the glass is touching the cold stuff inside and which glass it is. Touching some cold meat or such will increase the transfer of heat out of the glass and that will drastically affect the actual point at which the freezing begins. -- Why isn't there an Ozone Hole at the NORTH Pole? The one thing that no one has mentioned yet here is mass transfer. The hot water will loose heat faster at first, until it reaches the same temperature as the cold water, at which point they cool at the same rate. This implies that they should either freeze together or the cold water should win (depends on starting temperatures, surface areas, etc.) This assumes that all other things are equal... and they never are... If the containers are open (like an ice cube tray) the hot water is evaporating off much faster than the cold water. It is loosing mass and with it energy. Once it reaches the same temperature as the cold sample the formerly hot sample now has less mass than the cold sample and will cool faster. Try the experiment again with a cover over the containers. Of course, the next post I read will say the same thing... -- Joe -- Joseph M. Krzeszewski Mechanical Engineering and stuff Jack of All Trades, Master of None... Yet |
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