Well I'm considering biting the bullet and changing out my swamp cooler for
a refrigeration unit.
Before I even bother with getting quotes, one question keeps nagging at me.
Do these units use
recirculated air from the house or are they pulling all the air from the
outside? If they recirc, then
I might as well not bother as there's really no viable (monetarily and
aesthetically) way to add a
return air duct to it. It's clear I don't have a good understanding of how
these units work (I've been
in swamp cooler land for 25 years!). Just curious.
Do you have forced air heat system ?? If so, the AC fits within it and
use same existing ducting. Yes, it recirculates inside air, otherwise
would run continously and cost a fortune to operate. You normally close
all doors and windows, which can be its own problem re "stale" air etc.
I've had both systems; if swamper has been OK (ie dry climate like
Denver), you won't like AC.
Yup, I've got forced air. Trouble is, the Swamp cooler isn't located near
the furnace. The furnace supply feeds the
floors of the house while pulling from a couple large vents in the walls.
My swamp cooler is on the ground not near one
of these return grilles. So it looks like I'm SOL unless I want to do some
major stuff. In terms of Swamp vs. Refrigerated,
well that's a debate. I live in Albuquerque and the swamp cooler is OK but
not great. The last few years has seen higher than
normal humidities so at night it struggles. I'd prefer the refrigerated
route but I'll make do with the swamp it looks like.
You might try a different configuration with better controls, eg turn on
the swamp to cool recirculated house air when the indoor temp rises to 80 F
and turn on a small exhaust fan when the indoor RH rises to 65%.
This works in Melbourne Australia...
I too had the impression that Melbourne (vs Perth) was too humid for swamp
cooling, but I was wrong (have you ever been wrong? :-)
Reading more carefully, you might wonder what the exhaust fan does.
Then again, 22C is cool, but comfy (PMV = 0.007), with vel = 0.1 m/s and
clo = 1 insulation. Raising vel to 0.5 and lowering clo to 0.5 makes 35 C at
65% comfy (slightly cool, with PMV = -0.54, on a scale from -3 = cold to +3
= hot), according to the BASIC program in the ASHRAE 55-2004 comfort standard,
so he might have just used a ceiling fan on that day... 28C at 35% with clo
= 0.5 and vel = 0.5 is "slightly warm" in the comfort zone, with PMV = 0.23.
: A properly designed swamp cooler system can run with
: just the fan and no water, no need for extra ceiling fans.
If you're running it with a fan and no water, it's a ... fan.
Swamp cooling relies on the fact that water evaporation cools nearby air.
You pull outside air into the wet medium, and pump the cooler
and more humid air through the house. It then exits the house through open
windows (to the poster who recommended closing all the windows,
that's going to completely undermine the whole thing).
-- Andy Barss
anyone read Rex Robert's book? "Your Engineered House"
advocates natural air flow. Low vents and high exit vents to promote the
natural air flow as heat rises.
We love ceiling fans too. And a light color for the roof. the garage
sports a wind turbine. Cool!
If you see yourself in others, then whom can you harm?
Swamp coolers only work in LOW humidity areas, and they rely on cheap
access to water.
Desert Southwest is one such place.
The way to make them work better is to invest in a 1000psi to 2000psi
water pump and pump the water thru very fine nozzles to create a fog of
ultra fine water drops. These drops FLASH over to vapor phase when
they touch almost anything. Restaurants in the Desert Southwest use
this technique to allow patrons to eat dinner outside in the
summertime. Water quality is a concern as the nozzles are so tiny.
Reverse Osmosis filtration helps greatly with this issue, and minimizes
the mineral residue (ultra distilled water would work even better, but
is more costly)
About $5K for the base unit. Plumbing to the house is very very
similar to a Swamp Cooler as there is only a 1200CFM fan that blows air
across the refrigerated coils. Low power, runs off 120V 7amps peak,
averages about same as 100W light bulb. RUNS WITHOUT POWER for up to 3
hour, longer of an optional solar panel is attached. SEER is
calcualted at 983, YES NINE HUNDRED EIGHTY THREE!!
Homeowner is resposible for distribution of the refiregerated air. In
low humidity climates (less than 40% RH is the quoted figure), one unit
will cool about 1000 SQ FT. In high humidity climates (80% RH is
quoted) one unit will cool about 500 sq ft
Right now, I am sitting at 91F and for us a lower than normal RH of 44%
Heat index is 94F
The Solcool unit sounds like the two-stage evap coolers that were
promised five years ago. For one reason or other none of the systems
ever made it to large scale manufacturing. I see one big drawback for
SoCool - the $5K price tag, which is about 10X the cost of a similar
evap unit. I don't see them getting much demand on the retail side with
prices like that.
One wholesaler told me the HVAC companies hate evap coolers because
there is so little profit in them compared to regular systems. Maybe
with the the higher price point, they'll start pushing these Solcool
Agreed, in the Desert Southwest, where swamp coolers work well, they
both cool the house and add needed moisture. This thing expands the
envelope of applications outside the region where swamp coolers are sold.
The more valid comparison is to traditional AC units with which it is
price competitive. It adds refrigeration to a swamp cooler. This is a
very small refrigeration system, only about 1 pound of refrigerant is
used, versus 7-15 pounds in most residential refrigeration AC units.
1200CFM is a typical fan volume in refrigeration AC systems of the same
overall size class as this, they just do not recommend installing it in
a ducted house for some reason. Efficiency is very high, exiting air
temps are very low, air volume matches refrigeration, it looks better
"Then again, 22C is cool, but comfy (PMV = 0.007), with vel = 0.1 m/s
clo = 1 insulation. Raising vel to 0.5 and lowering clo to 0.5 makes 35
65% comfy (slightly cool, with PMV = -0.54, on a scale from -3 = cold
= hot), according to the BASIC program in the ASHRAE 55-2004 comfort
so he might have just used a ceiling fan on that day... 28C at 35% with
= 0.5 and vel = 0.5 is "slightly warm" in the comfort zone, with PMV 0.23"
You are simply too much, at clo=butt naked, anyone enduring a dewpoint
of about 81.5F is not going to be comfortable and would be seeking air
I endured a month of conditions similar to what you are postulating
during a prolonged power outage after a Cat 5 storm, and with a small
gen running ceiling fans and floor fans, it was no where near
After I salvaged a small window shaker AC that the gen could run, I
managed to pull the house down to 83F and 68% RH, about a 71.4F
dewpoint and compared to what it was like before with an 81.5 dewpoint
it felt good but it was still a far cry from comfortable.
In a dry climate it is a bad idea to use evaporative cooling on
recirculated air. It is more effective to directly cool the outside
air, force this cooled air into the home and allow room air to exhaust
outside. I proved this on your last flooded floor scenario, or was it
the inverted pool of pine, the cool tower
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