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

"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

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?

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?

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

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?