Free hot water
James S. Bassett
Does any one know where I can find a small freon water jacket
(desuperheater) to put on a frig & or freezer? as hot as the coils
get, they should be able to heat or preheat water for the house.
any ideas?
thanks
May the force live long and engage.
good luck
jb
R. Daniel Davies
In article <53oil2$h...@news.e-tex.com>, "James S. Bassett" <jbassett@e-
tex.com> writes
Not too sure what size you of freezer you have, or how little water you
use, but IMHO you wouldn't recover the cost of the heat exchanger for
many many years! And the environmental impact of making the heat
exchanger ( minimg, smelting, making etc) would be greater than the
conservation of energy warranted.
Will now retreat to my bunker and wait for the flack :).
--
Daniel Davies
The Eternal Optimist - though life should have taught me differently by now!
Tim Jebb
In article <Gge96AAz...@r-ds.demon.co.uk>, R...@r-ds.demon.co.uk
says...
>>Does any one know where I can find a small freon water jacket
>>(desuperheater) to put on a frig & or freezer? as hot as the coils
>>get, they should be able to heat or preheat water for the house.
>>any ideas?
>>thanks
>Not too sure what size you of freezer you have, or how little water you
>use, but IMHO you wouldn't recover the cost of the heat exchanger for
>many many years! And the environmental impact of making the heat
>exchanger ( minimg, smelting, making etc) would be greater than the
>conservation of energy warranted.
If your fridge/freezer is in a heated room with an independent thermostat
then you will automatically make use of the waste heat it produces.
Brian K Petroski
On 15 Oct 1996, Tim Jebb wrote:
> In article <Gge96AAz...@r-ds.demon.co.uk>, R...@r-ds.demon.co.uk
> says...
>
> >Not too sure what size you of freezer you have, or how little water you
> >use, but IMHO you wouldn't recover the cost of the heat exchanger for
> >many many years! And the environmental impact of making the heat
> >exchanger ( minimg, smelting, making etc) would be greater than the
> >conservation of energy warranted.
>
> If your fridge/freezer is in a heated room with an independent thermostat
> then you will automatically make use of the waste heat it produces.
Not sure where you are each posting from, but speaking for Minnesota
what you said is true in the winter when we are running the heater, but
the refrigerator runs hardest in the summer when we are also running the
air conditioner to cool down. The waste heat from the frig then puts an
extra load on the air condtioner and even more energy is wasted.
Brian Petroski
Just your stereotypical
polysexual,
bisexual
solitary pagan
from St. Paul, Minnesota
Tim Jebb
In article <Pine.SGI.3.91r.961015095220.11717S-100000@freenet>,
petr...@freenet.msp.mn.us says...
>
> Not sure where you are each posting from, but speaking for
Minnesota
>what you said is true in the winter when we are running the heater, but
>the refrigerator runs hardest in the summer when we are also running the
>air conditioner to cool down. The waste heat from the frig then puts an
>extra load on the air condtioner and even more energy is wasted.
I'm posting from Britain. We don't have summers (except in the
astronomical sense).
WalRog
James S. Bassett wrote:
>
> Does any one know where I can find a small freon water jacket
> (desuperheater) to put on a frig & or freezer? as hot as the coils
> get, they should be able to heat or preheat water for the house.
> any ideas?
> thanks
>
of the mechanical energy put into the coolant (pressurizing it) to force
it into liquid form so that it may expand (vaporization) allowing it to
absorb heat from the inside of the freezer. Any device attached on the
outside of the cooling coil directly will just make the compressor have
to work harder to fully ensure that the refrigerant is in its liquid
(vice gaseous) phase. The extra work done by the compressor will be
more than the energy recouped from the cooling coil (2nd law of
thermodynamics).
IOW (in other words), give it up. Its not feasible. If it were,
the frig would already have a device like that installed as an energy
conservation feature.
Walt
Sylvan Butler
WalRog ("wal...@GULF.NET"@pcola.gulf.net) wrote:
>Someone correct me if I'm wrong, but the cooling coils heat up because
>absorb heat from the inside of the freezer. Any device attached on the
>outside of the cooling coil directly will just make the compressor have
>to work harder to fully ensure that the refrigerant is in its liquid
This is a significant error I believe. Those hot coils on the
fridge/freezer are there to eliminate the heat absorbed from the cooler
interior. Anything you can do to suck heat from those coils will ease the
job of the compressor, not make it harder. Right?
sdb
Tooie
Sylvan Butler (syl...@cyberhighway.net) wrote:
The basic vapor refrigerating cycle is as follows (no I'm not going to
make an ASCII TS diagram):
1. The the liquefied vapor, under pressure undergoes irreversible
expansion (e.g. throttling valve) thus reducing its temp and pressure.
2. The vapor (or vapor liquid mix) then undergoes isothermal expansion
(absorbing heat from the "cold" region)
3. The vapor is then compressed by the compressor (work performed on vapor)
4. The superheated vapor is then cooled (by the cooling coils in
question) back to a saturated liquid. and we are back at point 1.
So to maximize performance, one would want to remove the greatest amount
of heat from the "cold" (fridge) reservoir with the least amount of work
(compressor). So assuming one could extract more heat from the vapor
during the condensation phase it would increase the amount af heat
absorbed during the expansion phase thus increasing the cycle efficiency
since -Qh = Qc - W.
A while ago (2 months?) there was protracted refrigeration discussion (Dietz
and Stewart? - correct me if I'm wrong) and the point came up the
refrigerator makers cautioned against keeping your fridge in an unheated
garage where the ambient temp could drop too low. My memory is fading,
if someone else remembers (or feels like going to Dejanews), could they
post the info.
tooie (must stop now - brain hurt)
Tooie
WalRog ("wal...@GULF.NET"@pcola.gulf.net) wrote:
: Someone correct me if I'm wrong, but the cooling coils heat up because
: it into liquid form so that it may expand (vaporization) allowing it to
: outside of the cooling coil directly will just make the compressor have
: to work harder to fully ensure that the refrigerant is in its liquid
: more than the energy recouped from the cooling coil (2nd law of
: thermodynamics).
Close but no cigar, the condenser take the superheated gas and (as the
name implies) and condenses back to a saturated liquid where it then expands
yada yada yada. Therefore the compressor will *not* work harder. It may
actually cycle less frequently and for shorter times since you are
removing more heat on the "hot" end and -Qh = Qc - W so you would get
more cooling for your work input (compressor).
There was a protracted refrigerator discussion about 2 months ago and I
remember the statement "Refrigerator makers caution against putting your
fridge in an unheated garage, etc." I don't remember the rest but
someone might.
: IOW (in other words), give it up. Its not feasible. If it were,
: the frig would already have a device like that installed as an energy
: conservation feature.
Not if it wasn't cost efficient.
The current issue of Popular Science (I know it's my second plug for the
mag but it was in the shitter at work) had a blurb about Lennox? having a
similar type system for a heat pump.
tooie
George Goble
Central air can be from 2-5 tons (HP).
There is some "free" heat, which can be recovered right off
the compressor discharge line. The initial hot gas off the
compressor can be 150F or more... What you do is to cool
down this gas, but not enough to condense it (desuperheat it).
If you condensed it, and needed 120F hot water, then your head
pressure would be over 400 PSIG, and a cause great load on the compressor,
the same as running on a 120F day outside.
Therefore by not "condensing", you can still recover enough heat for
domestic hot water (but not for space heating), and still use
an external condenser which operates at outside temp (or better
still on colder ground water or loop) to keep the head pressure
down (compressor load) to what it was before. Desuperheating
the freon, but not condensing it rejects only a very small amount
of heat compared to the complete condensation process.
Various companies make "desuperheating" attachments, to get
excess superheat into hot water.
--ghg
Brian K Petroski
On Fri, 18 Oct 1996, WalRog wrote:
> James S. Bassett wrote:
> >
> > Does any one know where I can find a small freon water jacket
> > (desuperheater) to put on a frig & or freezer? as hot as the coils
> > get, they should be able to heat or preheat water for the house.
> > any ideas?
> > thanks
> >
> Someone correct me if I'm wrong, but the cooling coils heat up because
> of the mechanical energy put into the coolant (pressurizing it) to force
> it into liquid form so that it may expand (vaporization) allowing it to
> absorb heat from the inside of the freezer. Any device attached on the
> outside of the cooling coil directly will just make the compressor have
> to work harder to fully ensure that the refrigerant is in its liquid
> (vice gaseous) phase. The extra work done by the compressor will be
> more than the energy recouped from the cooling coil (2nd law of
> thermodynamics).
> IOW (in other words), give it up. Its not feasible. If it were,
> the frig would already have a device like that installed as an energy
> conservation feature.
It has been done. Pre-1960 comercial refrigerators were sold;
primarily in Europe; with water heaters built into the mechanism. In the
U.S. energy is still considered so cheap that it's not much of an issue
to most consumers, also there are very few U.S. houses that don't have
central hot water heaters so there would be little call to have one on
the refrigerator. In short, their not being commercial available has
nothing to do with technical issues, only the fact that there is not
widespread demand for such a device.