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The heat from the vapor-compression refrigeration system is
used
to evaporate water, which preliminarily cools the coolant
water,
which is then further cooled through refrigeration.
The now cold coolant water is sprayed thinly into the room
onto
the ceiling where it is gathered as it
condenses, and taken to
the
side of the room. No fans, just an internal cloudy ceiling with
no
rain. For a hot day. The walls have passive dew condensers so
the
room is basically dry, giving the good natural feeling of
outdoors.
A few plants with LED lights complete the feeling giving off
oxygen and a nice fragrance.
== Adendum from the annotations ==
Its almost frozen water being sprayed on the ceiling. I'm not
looking for energy savings by an evaporator, I'm using regular
refrigeration with gas compression. The evaporator is in the
outside unit, and its just a preliminary step.
But the FAC device is not cooling the air, instead its almost
freezing water. and the frozen liquid droplets of water are
what are sent by spray to cool the room.
Passive liquid gathering and passive humidity extinguishers
are not that expensive and work pretty well. No need for
fans.
Wet bulb temperature
https://www.science...et-bulb-temperature
[doctorremulac3, May 23 2022]
Dewpoint and relative humidity
http://cimss.ssec.w...xwise/rh/page2.html
[doctorremulac3, May 23 2022]
Instachill
https://www.mitre10...v2-85w-10l/p/366253
Also, insta-damp... [neutrinos_shadow, May 23 2022]
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Annotation:
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//is gathered as it condenses, and taken to the side of the room// |
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You're essentially attempting cooling with water evaporation.
This will lead to close to 100% humidity. This will feel horrible
and turn your house into a mold farm. It will also not be air
CONDITIONING. The conditioning part, rather than just cooling
is the management of humidity. Dropping both the
temperature and humidity are synergistic features. |
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These are known as swamp coolers. |
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There are ads on TV here (New Zealand) for evaporative
coolers (linky). They're rubbish, of course. Effectively "here,
make your home damp!". Might work OK in a desert climate,
but not down here. Should be illegal to sell them here (damp,
badly insulated houses are a social health problem here). |
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They work quite well in Western Australia (which is, yes,
quite deserty), and I imagine they work quite well in Israel,
too, which is, I think, where [pashute] lives. |
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there is a way to wet a clay jar and place a wet towel over it so that the inside of the jar stays at two or three degrees if kept in the shade and the cloth stays damp.
There should be a way to control how much moisture is absorbed by the clay compared to the amount of coldth output by the descending air. |
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Still gonna need a fan to blow it around though.
Maybe solar powered... |
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I'm wondering if I can use an evaporative cooler to boost
the AC in my bedroom? Having a 3 floor house with insane
whole-house HVAC means that the bedrooms stay warm
while the basement gets all the cool air. Don't get me
started on how airflow is essentially managed with ill-
fitting doors. |
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Anyhow, if I put an evaporative cooler at the far side of the
bedroom it should lower the temperature at the cost of
increased humidity, but, that should just be removed by the
AC unit, so I'm just moving extra heat energy through a
water vapor cycle, it's not magic. But, will the extra
humidity offset the temperature benefit? |
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If your central A/C is effective enough to remove
that additional moisture in the room you put the
evap cooler in, it would be effective enough to
just
cool the room without the evap cooler. |
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In other words you're just putting additional load
on
your A/C system. And you might create a cooler
temperature area with high humidity that'll feel
much warmer than it is. Comfort is a
temperature/humidity thing. |
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You can look up climate zones where evaporative
coolers are useable but rule of thumb is the more
like a desert the better. A simpler rule of thumb is
they suck. |
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//if I put an evaporative cooler at the far side of the bedroom it should lower the temperature at the cost of increased humidity, but, that should just be removed by the AC unit, so I'm just moving extra heat energy through a water vapor cycle, it's not magic. But, will the extra humidity offset the temperature benefit?/// |
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So a swamp cooler with no hot air out? Not worth it. But swamp coolers in general are great for what they do. |
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If you're in the right climate zone. |
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//it would be effective enough to just cool the room
without the evap cooler.// |
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The problem is that it's whole-house HVAC. The system is
perfectly capable of cooling the house ON AVERAGE. The
problem is the bedroom is at the top. The basement gets
the coolest air, then the ground floor and the bedroom will
inevitably be hotter. Then the bedroom is specifically
heated, primarily by my unusually high thermal output, and
the sun hitting the bedroom wall/roof pretty much straight
from dawn. |
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If it were my house, I'd ritually sacrifice the whole-house
unit and all it's stupid great ducts and noise with a 30mm
cannon. Throw a good mini-split in the bedroom. I don't
know who thought the minimum unit of heating and cooling
should be EVERYWHERE all the time. But they need ritually
sacrificing with something slower than a 30mm cannon. |
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It's a STAGGERINGLY inefficient system. There's about 7-8
HVAC outlets and only 2 intake/returns. So there's air going
into some rooms but having no path back. The solution, and
this makes my UK friends laugh, is to just cut the door so
that there's a 1-1.5" gap under it. Of course that means that
the outlet pressurizes the room slightly, and pushes the
COLDEST air out under one door, under a second door and
up into the return/intake. Of course it blows all the dust
into the rooms with the return as a nice by product. |
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What I'm going to do, is ignore the rules on window AC
units. Then see if I can borrow a ladder. I have a couple of
spare diaphragm pumps and some tubing. A few gallons of
water sprayed over that portion of the roof through the
night/morning should have a powerful cooling effect. |
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I also noticed that my window AC unit deliberately pools
the condensation water in the condenser section and sort of
allows the fan to splash it around the place. It will be more
efficient that way, but I think I can further enhance it, a
small pump drawing from the (now blocked) drain port that
recirculates and drips evenly over the condenser fins should
work better. Even better still if I can work in a way of
slowly metering in some of the not-stolen at all industrial
alcohol. Keeping it at ~10% or so should be more efficient
and super safe. |
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Anyway, the point about the evaporative cooler being that
I'm trying to specifically cool the hottest room in the house.
The HVAC IS effective enough, it's just that to get the
bedroom to a sensible temperature, I'm spending money
cooling all the parts of the house I'm not in to an
unreasonable degree. |
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Assuming the A/C is properly sized, you need to air balance
the system. |
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First off establish your flow paths from the diffusers
(outlets) to the returns. Slots under the doors are better
than nothing, but you can also put slotted panels in the
walls or doors. This might
effect soundproofing of the bedrooms so just don't have
loud sex. You might have to stop having marital relations all
together, they teach you this on day one in HVAC school.
(not
that I've ever been to HVAC school, but I assume they go
over that in the introductions) |
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Then get yourself a anemometer to measure your airflows
through the various supply vents. If you don't want to do
that, dhunno, maybe you can just tie a ribbon to the
various outlets and look at the angle of their fluttering.
Bigger rooms need more fluttering, smaller less. Just
thought of that so don't know if that would work but better
than nothing I suppose. |
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The further from the unit the vent is the more static
pressure it has to overcome, that's just the resistance to
airflow through the ducts. Close up the vents closer to the
unit and open up the ones further till you get reasonably
balanced air flow through all of them. |
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Consider upping your insulation, attic first, some nice R-30
batt insulation instead of blow in or wimpy R-11. Then if
you're really rich put in double glazing, that's a big deal and
you can justify it by lowering your energy bills. Probably
get some breaks from the city too for upping the energy
efficiency of your home. |
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Used to design this stuff when I was a teenager. Don't know
how much of the environment I've saved by designing more
energy efficient houses but it probably added up over the
years. I don't like to use the word hero, but hey. If the word
fits, who am I do disagree? |
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And by the way, goes without saying just close up the vents to
the rooms you're not using. Don't want to stagnate your air
flow too much and freeze up your evaporator coils but sounds
like that's probably the least of your worries. Point is an un
air-balanced system is basically just a noise maker. |
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Clearly what's needed is distribution of liquid nitrogen throughout the house. |
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Liquid helium would be better. |
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Agree with everything doc said. And tape up your
duct joints. |
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I run just the hvac fan all night to move the cold air
from the basement to the rest of the house and it
does a great job freezing us out by morning, to
where I have to turn the system to heat and set the
heat to a minimum point. |
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Its almost frozen water being sprayed on the ceiling. I'm
not looking for energy savings by an evaporator, I'm using
regular refrigeration with gas compression. The evaporator
is in the outside unit, and its just a preliminary step. |
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But the FAC device is not cooling the air, instead its almost
freezing water. and the frozen liquid droplets of water are
what are sent by spray to cool the room. |
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Passive liquid gathering and passive humidity extinguishers
are not that expensive and work pretty well. No need for
fans. |
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//And tape up your duct joints.// |
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Yes. And while you're up there wrap them in insulation as
well
if they're not already. |
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Pash, nobody likes outside the box ideas more than me, but
I've spend enough years in my youth working with humidity
extinguishers
to know that's a much cooler name for what they currently
call dehumidifiers. |
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Bunning this for that alone. [+] |
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//Close up the vents closer to the unit// |
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I was reluctant to do this, since we had coil-freezing
problems in the past. But I'll give it a try. I can definitely
close off 2 bathroom vents at night, since the bathrooms
are in the corners they're particularly warm... closing the
bathroom doors effectively turns the rooms into insulation. |
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Ultimately, and irritatingly, the house is not mine. If it was,
man I have ideas. Houses follow the basic rule that: the
more important it is, the worse we are at it. They basically
don't change, and often, when they do it's for the worse. |
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At the very least I'd have an air handling system, filtered
intake that keeps the house at mild positive pressure with a
heat exchanged exhaust. That way, you actually get some
air exchange in a managed way, not just whatever leaks the
drier is pulling air through. |
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Still, there's something deeply odd about our row home, it
requires ludicrous amounts of cooling, yet heating is totally
unnecessary until we get sustained temps below 30F. I've
been in both neighbors houses and it's not like they're
maintaining 93F. I've checked the adjoining walls with an IR
thermometer, it's not remarkable. The house just is warm,
best current hypothesis is that we're on a very small
volcano. |
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//Close up the vents closer to the unit// |
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//I was reluctant to do this, since we had coil-
freezing problems in the past// |
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Yea, just hire a contractor with the proper tools to air
balance
the system. I didn't just tweak a vent here and a vent
there, I got all the numbers, ran the calculations and knew
how much CFM should be coming out of each point and
adjusted them accordingly. |
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//Still, there's something deeply odd about our row home,
it requires ludicrous amounts of cooling, yet heating is
totally unnecessary until we get sustained temps below 30F.
// |
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Guessing you're slab on grade. That's a big passive thermal
storage element. So if you're hot during the day, that slab
retains the heat and radiates it back at night. |
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But I'd just hire a contractor to come out and evaluate your
system. I can do it for... one million dollars. |
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//Guessing you're slab on grade.// |
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Oh no. Amateurish thin concrete poured onto dirt in the
basement. And I'm talking about the winter. The house can go
weeks in the 30's F range and not need heat. It's my current
biggest mystery along with how plastic bags spontaneously
inflate in freezers. |
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Yea, that's slab on grade. Just a fancy name for concrete on
dirt. |
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Easier to charge more with the name that people don't understand. Can get more for "We survey and laser level the construction envelope footprint, excavate, rebar and pour the slab, level and build up the stemwall…" than "We dig a hole and pour some shit in it." |
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heh, so If i disconnect the AC ducts, allow it to run in the
basement sucking heat out of the earth and move the
condenser into the dining room, I can have a DIY redneck
ground source heat pump like them fancy Scandiwegians? |
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I'm going to say... yes, just because I'm curious to see what
happens. |
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