
Hacking Portable Air Conditioners - p1mrx
https://pmarks.net/ac/
======
slig
Very interesting video from Technology Connections
<[https://www.youtube.com/watch?v=_-mBeYC2KGc>](https://www.youtube.com/watch?v=_-mBeYC2KGc>)
"Portable Air Conditioners - Why you shouldn't like them".

~~~
gruez
>Very interesting video

The content might be interesting, but it's way too long. The guy goes on way
too many tangents and adds way too much filler. You probably can boil the
whole video down to a few bullet points, yet it's 16 minutes long.

~~~
hombre_fatal
On the other hand, I like his long-form video entertainment. I'll eat lunch
while watching one maybe. Not everything needs to be optimized into
bulletpoints.

~~~
copperx
I had a deja-vu, I thought I had read this exact comment before in HN. Have
you used the same words before?

~~~
gruez
[https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...](https://hn.algolia.com/?dateRange=all&page=0&prefix=false&query=Not%20everything%20needs%20to%20be%20optimized%20into%20bulletpoints&sort=byPopularity&type=comment)

Seems to be unique

------
refurb
I'm impressed as hell that the customer service guy and engineers at the
company were so willing to answer technical questions!

~~~
jaggederest
It looks like Edgestar is a company that makes a pretty wide variety of HVAC
equipment and prioritizes support. That makes a lot of sense for larger
orders, especially for a design/build company. I love finding these kinds of
companies, that focus on customer service. It's what made Amazon so special,
at least back in the day.

Anyone else know of other companies in this vein?

~~~
tgtweak
A few that I go out of my way to recommend: Logitech, Fellows, Dyson and
Breville.

Each has just straight up sent me a new unit or full replacement part when the
previous one failed with no rma or warranty check - none of that nonsense just
great service. Dyson support even sent me full factory service manual for the
unit 5 years after it was discontinued (and 7+ out of warranty) since I wanted
to troubleshoot a power supply issue which ended up working fine after
resoldering the main power cord to the power board.

These companies are increasingly rare.

~~~
gautamcgoel
I had the opposite experience with Dyson. A $350 Dyson vacuum I bought stopped
working a month after I bought it. I determined that a faulty battery was to
blame. When I called customer support, they tried to sell me a new battery (I
forget the price they quoted me, I think it was at least $50). It was only
after I protested that they agree to send me a new battery for free. I got the
strong impression that their company policy was to first try to sell a
replacement part to take advantage of rubes; only if the customer refused to
pay would they offer a new battery for free. Really disappointing quality and
service from such an intensively marketed brand. It was especially annoying
since the vacuum came with this pompous little booklet about "the Dyson
story", how Dyson represents British engineering at it's finest, etc.

~~~
tgtweak
That's really too bad - my own experience was with a dyson DC21 canister that
I bought in 2008 - after 6 years the power head started intermittently turning
off while cleaning. They sent an entirely new power head no questions asked.
It kept working for another 6 years without any other issues, then it just
refused to turn on one day. I called and asked if they could service it and
they said sadly the unit was discontinued several years ago but that they
could send me the factory service manual and that the issue was likely with
the connection between the reeling cord assembly and the main board. Sure
enough, I guess reefing on that cord for 12 years caused it to come loose - 30
minutes later it was back up and running and I still use it to this day. Worth
noting that this thing still cleans as strong today as it did back then.
Perhaps Dyson Canada is different than US - I've seen a LOT of refurbished
dysons on various marketplaces so I'm guessing they are not flawless - the
fact there are so many refurbs however leads me to believe they are exchanging
them without asking questions and that they are quite serviceable.

------
leoedin
This is interesting. We collectively spend _so much_ of our energy on heating
and cooling buildings, and there's very little change happening.

The problems identified in the article are such low hanging fruit. Everywhere
you look in residential housing there's huge efficieny gains to be made, but
very little effort is going in to making them.

I'd love to find ways we can use technology to make housing more efficient. We
need to - it's such a crucial pillar in dealing with climate change, and the
vast majority of housing is so comically inefficient. The single tube air
conditioners mentioned in the article are just the icing on the cake of all
these massive energy wastes we accept because they're marginally more
convenient. Does anyone know how to fix this?

~~~
esaym
>and there's very little change happening.

There's honestly a lot happening and changing. Obviously you won't see it by
buying "HVAC" junk from a box store. What this person should have done is paid
an actual HVAC tech to install a ductless mini-split [0]. It would have been a
heck of a lot more efficient. He states his one unit is drawing 10 amps (110
volt I assume). Whereas my american standard 4 ton (48,000 btu) unit draws 10
amps as well (240 volt) and cools a 2200 square ft house in 100+ degree texas
weather with an electric bill usually not higher than $120 per month (1200 -
1400 kwh or so).

By comparison, at my old house (which was half the size, 1100 sq ft) with a
much older 12 Seer unit, my electric bill was regularly over $200. I measured
that unit at drawing 18 amps (at 240 volt) and it was only a 3 ton 36,000 btu
out door unit. The latest and greatest 21/22 seer units are even more
efficient than my current one mentioned above (which is probably only 17
seer).

[0]: [https://www.americanstandardair.com/products/heating-and-
coo...](https://www.americanstandardair.com/products/heating-and-
cooling/ductless/)

~~~
p1mrx
Installing a mini-split would be a year-long project, including HOA
negotiations, architectural design, electrical load calculations, city
permits, and invasive construction. It's not the sort of thing you'd want to
attempt at the beginning of a pandemic (or ever, for most people.)

Given the orders of magnitude less work required to find a product and click
"Buy", it'd greatly benefit society for portable A/C manufacturers to compete
on efficiency.

~~~
troydavis
> a year-long project, including HOA negotiations, architectural design,
> electrical load calculations, city permits, and invasive construction

Obviously only you know your situation, but just in case any other readers are
considering a mini-split: it doesn't have to be this way and it typically
isn't.

From firsthand experience installing Mitsubishi mini-splits in multi-unit
buildings in very regulated cities, a typical condo installation takes 2 days,
including running power from an electrical panel that's not in the unit. A
reasonable HOA can often answer in a week or two unless you're the first
person to install a mini-split in the building. Larger buildings often
recommend specific HVAC contractors. Your contractor will apply for HVAC
and/or electrical permits online with very basic drawings; they're often
issued immediately ("over-the-counter"), subject to field inspection. There's
generally one inspection after it's installed. A good contractor will handle
almost all of this.

Basically, it can be complicated but it doesn't need to take a ton of calendar
time. Other than cost and needing outdoor space for the condenser, the hardest
challenges you & your contractor will encounter are running new electrical
circuits from the panel and draining condensate from the indoor head.

~~~
balfirevic
> are running new electrical circuits

Why is this needed? Is it because the electricity in the US is at 120V? Over
here (Europe) you can just plug the cable from the indoor unit into the
electrical outlet.

~~~
masklinn
I learned recently that US housing generally gets 240V, but most circuits use
neutral and a single hot to get 120V which is the standard mains in the
country, and you'd run dedicated 240V for large appliances e.g. furnaces,
dryers, electric oven, induction cooktop.

The AC would not have been planned for when designing the original circuits,
so you would need to add a 240V circuit for it unless you put it in a room
which already had one.

As the others have noted, since it's a high-power unit anyway you'd really
want to have it on its own circuit to avoid adding too much load on the
circuit. So even in europe you probably want a circuit exclusive to the AC,
meaning you may have to run a new one unless an AC circuit had originally been
run "just in case" (and even then it might not have been run to the room you
wanted it in e.g. maybe the original builders put the circuit for an eventual
AC in the living room but you want it in the bedroom you converted to a
study).

------
noipv4
The minimum standards for a portable AC should be a dual-hose one. Single hose
ACs make no sense; it is like throwing a lot of efficiency away, just to look
a bit sleeker and a very slight increase in installability and mobility.

Also who in their right minds in Europe decided to rate single hose AC at A+,
or A efficiency levels; the same as a good split AC? Single hose portables
should all start with an F to educate a potential customer as to how dumb this
device design is.

[https://www.galaxus.ch/en/s2/producttype/air-
conditioners-28...](https://www.galaxus.ch/en/s2/producttype/air-
conditioners-280?tagIds=40-62)

~~~
Bombthecat
I want to buy dual hose, but no luck so far. They are just not sold...

~~~
pessimizer
I'm pretty sure the ones listed in the article are on Amazon. I bought my
Whynter ARC-14S from Amazon. It's very loud, but it gets things cold. They're
not cheap.

edit: loud like air-whooshing loud, not like vibrating compressor loud.

~~~
Bombthecat
Not in germany :)

------
dencodev
I have spent a LOT of time researching using a small window AC unit converted
to work in a camper van without cutting a giant hole in a wall. There's a
fellow on Youtube[1] that did this successfully, and he's the only known
example of it that I've seen, and he was only able to because was he a
professional HVAC technician and had several unique tools you'd never own if
you weren't an HVAC tech.

Essentially what I'm aiming for is this:
[https://www.cruisencomfortusa.com/hd-
series](https://www.cruisencomfortusa.com/hd-series)

which is a perfect product, except that it costs $4000 and still uses 20% more
power than some of the smallest window units. It's ridiculous that the major
difference between this $4000 unit and a $150 window AC is that the $4k
version has a rubber hose connecting the compressor to the condenser coils
instead of the typical thin copper pipe. I am sure there are other differences
- it uses better components that are more suited to a moving vehicle with
shocks and vibrations, has a strong compressor to deal with the longer hose
length, and is already adapted to run off of 12V. But a $3850 price difference
is ridiculous.

As the fellow on Youtube has shown (it's been in his camper van for years
without a problem) there's really no reason the components from a $150 window
unit won't work.

Whenever I finally do a camper van build I'm going to find an HVAC tech who
can help me with a couple steps (mostly removing and then re-adding
refrigerant) and convert the copper pipes to PTFE lined stainless braided
hoses attached to SAE fittings. It may not work, and I've heard finding an
HVAC tech to work on weird projects is very difficult, but I want to give it a
try.

[1]
[https://www.youtube.com/watch?v=AXgHIrFqm9o](https://www.youtube.com/watch?v=AXgHIrFqm9o)

~~~
elliekelly
What about the mayor bloomberg route?
[https://m.youtube.com/watch?v=P5vJWHMlHHg](https://m.youtube.com/watch?v=P5vJWHMlHHg)

~~~
dencodev
A lot of camper vans do this - it just looks awful, destroys any stealth
value, has to be moved in and out of the opening any time you start driving,
and takes up a ton of internal room when not deployed.

------
wiremaus
The magic product the writer is looking for does exist — somewhat. It's those
Euro style mini-split heat pumps, that pump coolant through an external unit.

Up front cost is higher, but the efficiency gains are huge, and they can
cool/heat much faster.

~~~
peteretep
> Euro style

The only place in this wide world I’ve seen anything other than split units is
North America, so “Euro style” seems an odd description.

~~~
wiremaus
That's accurate: they're the standard in much of the rest of the world due to
their lower operating costs.

I was using "Euro" only to help people picture the things, it's a common way
I've heard them described.

------
BeetleB
Years ago I bought a used (portable) evaporative cooler for $25. When the
temperature is not higher than, say, 85F, it is very effective in the day. I
do not live in a dry climate. During the day it's 20-50% humidity, and gets
high at night. It's clearly a lot less effective at night, but it's usually
cool anyway at night.

Window air conditioners work great, but if you can't have that, consider an
evaporative cooler if you can get one at a decent price. Do make sure you get
one with a decent air flow as well as a decent sized tank (e.g. one where you
can run it all night without the water running out in the middle).

Probably won't work well in humid Midwest or South/East.

~~~
axaxs
Yeah, swamp coolers are great in theory, but they do nothing at all in areas
that most desperately need cooling.

~~~
grecy
They work brilliantly in places with low humidity by high temps - i.e.
Arizona, California and my personal experience - towards the middle of
Australia.

~~~
masklinn
Yeah they will work nicely in any "dry" desert. They do require access to
significant amounts of water, though with the nice side-effect (for the
context) that they also act as humidifiers,.

------
starpilot
The temp vs run duration doesn't seem that meaningful. It shows the first 3
minutes of runtime, and doesn't show if all configurations reach equilibrium
performance after that. It looks like they might. These things are usually run
for _hours_ , is there a chance they'd have similar cooling performance at
that length?

The insulated hose is something I'm exploring myself. There's insulated
ducting like this: [https://www.homedepot.com/p/Speedi-Products-6-in-x-12-ft-
Ins...](https://www.homedepot.com/p/Speedi-Products-6-in-x-12-ft-Insulated-
Flexible-Duct-with-Metalized-Jacket-R8-FD-12R8-06/203393272?MERCH=REC-_-
pipsem-_-203393287-_-203393272-_-N) but it looks terrible. I'm kind of worried
about having fiberglass being in my living space like that, the PPE is
significant [https://homeguides.sfgate.com/safe-ways-handle-fiberglass-
in...](https://homeguides.sfgate.com/safe-ways-handle-fiberglass-
insulation-82010.html) and I'm pretty sure my cats would shred it up. I'm
leaning toward adding reflectix sleeves with gaps so that the hose is
flexible.

~~~
Vendan
It seems to not be considering "can it reach a temperature", but "how much
heat can it remove in 3 minutes", which, IMO, considering constant power
usage, is more valuable for "how efficient is this"

~~~
sokoloff
For that short a period, it seems like the mass of the condenser would be
relevant and disturb any extrapolation to efficiency from a run time which is
not largely steady-state.

------
lifeisstillgood
Anyone else "back in the day" would buy portable air conditioners from the
hardware store and sling them into your server broom cupboard in an attempt to
keep things from overheating.

It got so boring when we rebuilt with proper falso floors ceilings and real
racks.

~~~
walrus01
There's still a number of small ISP and telecom infrastructure sites cooled by
setups like a pair of Haier consumer grade, ductless split 18000 to 24000btu/h
units. Not an uncommon setup for places like small shelters at hilltop and
mountaintop radio sites.

------
arkanciscan
It's not really a hack is it? More like a fix or an optimization. I was
excited for a second cause I have a single hose portable AC and I've been
thinking about "hacking" it with an intake hose.

However, the more I use the thing the more I realize that there's nothing
wrong with it. Since the rest of the house isn't air conditioned there are
open windows and fans throughout. Air is more likely to be drawn in from the
rest of the house than through the cracks to the outdoors. Might be an issue
in a sealed studio apt, but in our leaky shoebox of a ranch style home, it's
hardly the biggest inefficiency.

------
Rebelgecko
Hooking it up to the Nest was really clever. I've dabbled a bit with IR
control of similar units, but that really takes it to the next level

~~~
p1mrx
There's really nothing Nest-specific in the design. It just takes two
components (AC input optocoupler and resistor) to sense the 24VAC output from
any standard thermostat.

Connecting to the Nest was probably easier than turning an ESP32 into a proper
thermostat.

The hardest part of the whole project was figuring out how to read a clean
signal from a photodiode.

~~~
flak48
Just read your post and just wanted to say I'm in absolute awe!

------
ajb
This is really cool. Maybe there is a market opening for an open, hackable
aircon unit?

One thing I've long wanted to try with mine is use 'heating mode' as a quieter
version of cooling mode. They work the same - the unit just runs backwards,
with the cold air coming out of the tube instead of the vents - so in theory
you can cool your bedroom without having the noisy aircon in the same room.
But the thermostat doesn't work properly in this case, because it thinks it's
trying to raise the temperature of whatever room you put it in, not cool the
other end of the tube, so for this to work properly you need to hack the
control board.

~~~
userbinator
_Maybe there is a market opening for an open, hackable aircon unit?_

In the US, I think the EPA would not let you...

...not that it stops people all that much, as a YouTube search for "DIY AC"
will show.

~~~
derefr
> In the US, I think the EPA would not let you

In Canada, you need to be a licensed something-or-other to purchase or own
compressed CO2 canisters. This put SodaStream in an awkward position when
entering the Canadian market, since their whole business model is built on
selling people CO2. But they figured out a workaround: in Canada, you don't
_buy_ their CO2 canisters; instead, you "join a club" that allows you to
_borrow_ CO2 canisters (and/or refills the ones you have), and then _charges_
servicing fees for "their" canister equipment. (Sort of like how a catering
company would rent a helium tank.)

I wonder if something similar could be done for refrigerant-supply licensing
in the US.

~~~
xelan
Wait, what? I am in Canada and I have a couple of 5pound CO2 canister for home
brewing and a modded sodastream to accept any CO2 canister. Where did you find
this information?

I even get it filled up at the corner store lol.

~~~
derefr
I don't know if it's true today, but back when I had a SodaStream (~5 years
ago), a "purchased" SodaStream CO2 canister came with a printed copy of this:
[https://www.sodastream.ca/en/assets/ulc.jpg](https://www.sodastream.ca/en/assets/ulc.jpg)

~~~
nucleardog
Yeah I don’t think that has anything to do with the government. That’s just
them trying to prevent you/scare you away from refilling the containers
yourself.

Paintball guns run on CO2. You don’t need a special permit to own a paintball
gun. You can pick up a paintball tank on eBay and run down to Canadian Tire or
any paintball field and they’ll happily fill it up for you. Or at least they
used to — it’s been a while for me.

------
mehrdadn
Tangentially related, but how do you find portable ACs that work reasonably
and reliably? I always found it so hard to search for them because it always
seems like the reviews on these are difficult to trust. I've had at least one
bad experience with one of them (single-hose) where it would just blow warm
humid air sometimes, which was strictly worse than not running it at all. (At
least something that might cool the air nearby consistently would be something
useful, even if it can't cool the whole room.) I realize single-hose is
probably a bad idea but somehow I don't have much faith in dual-hose either.

~~~
starpilot
Wirecutter has never let me down:
[https://www.nytimes.com/wirecutter/reviews/the-best-
portable...](https://www.nytimes.com/wirecutter/reviews/the-best-portable-air-
conditioner/)

Interestingly, in their tests, they didn't find dual-hose models to work much
better than single-hose, unless it's extremely hot.

~~~
mehrdadn
Thanks! I did look at Wirecutter actually, but for example the Amazon reviews
for LG LP1419IVSM appear a little scary -- average 3.5/5, with 20% of them
being 1/5\. Have you actually had good experience with portable ACs from
Wirecutter recommendations, or did you just recommend them in general?

~~~
rtlfe
I don't know about portable, but FWIW the Wirecutter window AC reviews don't
match my experience at all. They say that Friedrich is louder than LG, which I
know to be false because I have one of each running in adjacent rooms.

~~~
TwoBit
Wirecutter reviewed the same models that you have?

------
chx
> The point of connecting portable A/Cs to a Nest is:

> The usual "smart" stuff that Nest provides

Reminder: [https://michaelblume.tumblr.com/post/169525456166/tech-
enthu...](https://michaelblume.tumblr.com/post/169525456166/tech-enthusiasts-
everything-in-my-house-is-wired)

> Tech Enthusiasts: Everything in my house is wired to the Internet of Things!
> I control it all from my smartphone! My smart-house is bluetooth enabled and
> I can give it voice commands via alexa! I love the future!

> Programmers / Engineers: The most recent piece of technology I own is a
> printer from 2004 and I keep a loaded gun ready to shoot it if it ever makes
> an unexpected noise.

> Security technicians: _takes a deep swig of whiskey_ I wish I had been born
> in the neolithic.

------
saboot
One thing with dual hose ACs that I would also like to see improved is an
extension of the exhaust hose. For me often the hot air will heat up the
window which then radiates heat back into the room. We do have 1980s aluminum
framed windows, which really makes that problem worse.

I did find a big improvement in getting duct insulation and wrapping the
exhaust hose in that. For the window portion, I cut out an insulating foam
board to mount the hoses, and taped the outside edge with reflecting tape.
It's keeping my large bedroom around 76, unless it gets above 95 and will
start creeping to low 80s.

------
dirtyid
There's some pretty basic form factor changes that can go a long way to just
eliminating portable units, i.e. these new U shaped designs.

[https://www.youtube.com/watch?v=0NELPBxrgsE](https://www.youtube.com/watch?v=0NELPBxrgsE)

Wonder why there's no "n" designs for obstructive light. Regardless, there's
no reason for portable AC, even duo hose ones due to length limitations on
hose before inefficiencies. More effort into easy to install window / split
units please.

------
082349872349872
With WFH widely accepted, I wonder if transhumance will regain popularity?

(In my area, the herds would move between valley floor, mid-mountain, and
alps. Most people would move between valley floor and mid-mountain. Peasant
banking started here when everyone sent their cows up to the same alp, and the
resulting cheese had to be divvied up between the owners and the alp crew.)

[https://en.wikipedia.org/wiki/Transhumance](https://en.wikipedia.org/wiki/Transhumance)

------
TwoBit
Dual hose units are increasingly hard to find. Hardly anybody makes them
anymore. I've read in a couple places that they don't work great, despite that
window units do.

~~~
p1mrx
The thing is, dual-hose units _could_ work great. The concept is theoretically
sound, but nobody's trying to engineer them properly.

~~~
AshamedCaptain
I really doubt that. Most likely the vacuum efect is overrated as hell
compared to the other various inefficiencies (e.g. not all the compressor's
heat being vented outside)

I paid extra for a dual hose unit and find myself almost never using the
second hose at all. The effect is negligible and not worth the small effort of
picking up the second duct from the closet.

And on my unit (trotec) you _can_ close the intake vents with a simple switch
if you install the 2nd hose, so its not like all manufacturers are idiots.

~~~
p1mrx
> The [vacuum] effect is negligible

How did you determine that the effect is negligible? A single-hose A/C should
actually _blow colder air_ locally, because it's using cool interior air to
cool its condenser. The problem is, it's also throwing cool interior air out
the window, which is thermodynamically insane. Every unit of air it expels
must be replaced by hot air somewhere else in the building.

> e.g. not all the compressor's heat being vented outside

This is an engineering problem; the compressor should be well-insulated from
the room (thermally and acoustically), and cooled using outdoor air.

~~~
AshamedCaptain
(I can no longer edit at this point)

> How did you determine that the effect is negligible?

The power bill measures overall how much time the compressor spent running for
the same preset, and there's little difference between two hose and one hose
mode. I'd presume this is the most effective efficiency measurement I have.

> A single-hose A/C should actually blow colder air locally, because it's
> using cool interior air to cool its condenser.

Usually it feels as if the air _around_ the ducts/behind the compressor is
warmest, rather than around the room's ventilation grills which is where I
suspect you would notice warmness if there was a significant negative pressure
issue (yes, this is modern France building so I'm forced to keep an aperture
to the outside for air renewal, even though otherwise the isolation is
topnotch).

> the compressor should be well-insulated from the room (thermally and
> acoustically),

This obviously makes sense, but it is much easier said that done. People still
want to carry the thing between rooms (and/or carry it themselves to their
homes) which is why it is a mobile air conditioner in the first place.

------
danbr
I attempted something similar, at least on the nest side of things. I quickly
realized the nest wouldn’t recognize any attached equipment unless connected
to a 24vac line. I always wondered how the nest derived DC power to charge its
internal battery when a common line was not used. Maybe I’ll research this
some more and try again.

~~~
p1mrx
The Nest can sort of trickle charge itself through its relay outputs, but for
reliability you really want to provide 24VAC between R<->C.

To attach equipment, you can connect a 24VAC-friendly load between (e.g.)
Y<->C or W<->C.

~~~
danbr
Didn’t know about the trickle charging, neat!

Problem with attaching a load is that if you want to build a standalone unit
with the nest, you’ll need some type of inverter when powered off DC, or
perhaps a simple sine wave generator? I’m more of a digital, DC power guy.

~~~
p1mrx
Yeah, you need a sine inverter, either 24VAC, or 120VAC with a 24VAC
transformer.

There might be a way to trick the Nest into running on something closer to DC,
but I could only guess.

------
tgtweak
Just get a mini split and save yourself a few hundred man hours - this being
the engineering equivalent of polishing a turd.

Even a poor mini split will outperform these in terms of efficiency and
silence - and they can be wired directly to a nest or simple thermostat.

~~~
spacedcowboy
Just installed a Carrier (40MAQB12B1 / 38MAQB12R1) mini-split in the shed,
which I had spray-foam insulated (and then I installed drywall) beforehand.
This for the work-at-home thing which we're doing for at least another 6
months...

The difference between the loud portable unit and the blessed silence and
efficiency of the mini-split is chalk and cheese. There really is no
comparison.

The mini-split cools the shed down to 72, where I have to increase the
temperature to stay comfortable, in about 4 minutes. It's even silent outside,
and these units will provide 12k BTU of heating or cooling, so it'll be useful
in winter too.

~~~
tgtweak
Yep. Had a Fujitsu halcyon 18,000btu and you could not tell it was on. Prior
to that I had a delonghi "penguino" 13,000btu portable AC (it cascades water
over the hot side of the condenser and ejects it out of the exhaust line)
which is light-years ahead of these models in terms of efficiency and quality
and it struggled to cool 500sqft while the mini split can easily sustain
temperatures in 1200sqft. This particular model can also heat with exterior
temperatures as low as -26C (~ -15f) which cuts a ton of heating costs - heat
pumps provide ~3x more heat per watt than baseboard heaters. Add to this the
fact it's nearly inaudible inside or out and I can't imagine why someone would
choose portable ACs over this - even high end ones. The installation is quite
straightforward despite requiring a technician to do the refrigerant part and
confirm the electrical setup.

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fomine3
Air conditioner's compressor without PWM inverter is less controllable so
makes it inefficient. Here in Japan only mini-split type air conditioner
features PWM inverter and it's dominant.

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Zigurd
If you have been getting Whole Foods deliveries, you may have quite a few
insulated bags that could be repurposed, with some gaffer tape, to insulating
cabinets and ducts.

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gpm
Could you use one of these units to many a diy fridge? Freezer? Or are they
somewhat tied to reducing the air temperature to only room temperature?

~~~
p1mrx
This particular model will not cool below 60F/16C. Even if it could, the point
of a portable A/C is to avoid cutting holes in the wall, which is not relevant
if you're building a custom enclosure.

In theory, you could build an insulated box with a mini-split or window/wall
unit, but they're probably all optimized for cooling a large space, not
freezing a small space.

Tech Ingredients made a DIY fridge (and a freezer in later videos) using
peltier coolers:
[https://www.youtube.com/watch?v=YWUhwmmZa7A](https://www.youtube.com/watch?v=YWUhwmmZa7A)

~~~
gpm
That was a super interesting video, thanks!

~~~
patrickk
[https://www.youtube.com/watch?v=7w4rg3UcsgI](https://www.youtube.com/watch?v=7w4rg3UcsgI)
also worth a watch, trying to devise a different type of AC system

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mc32
Author mentions Climax-Air as having decent units but out of stock. I think
the Toyotomis are also pretty good in this class of A/C.

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dzhiurgis
What I always wondered is why these units don't come with heat recovery
ventilation system inside. Seems obvious.

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nullc
There are inexpensive minisplits available, they're often a much better choice
than two-hose portable ACs.

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euroclydon
That would be a great aftermarket product to hook up Nest to portable air
conditioners.

~~~
hinkley
I tried to look for something equivalent for those in-wall space heater units.
They run on a different voltage, because of course they do.

I think the boxes were like $40, but they looked like electrical junction
boxes. Clearly meant to be buried in a wall cavity.

~~~
quickthrowman
Junction boxes are not meant to be buried in a wall. In fact, any junction box
containing wire (not just connections/splices) is required to be accessible
without removing any part of the building per the National Electrical Code.

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curiousDog
Whoa is this Paul Marks from Purdue? Haha, long time, I miss the Dtella days!

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oogetyboogety
Love the "plant growing forum" reference

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sizzle
What kind of toxic VOCs do these indoor units leak out?

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anonu
These things should be banned in my opinion. They're so inefficient and never
get the room down to a decent temperature.

~~~
denysvitali
Unfortunately I guess they're the only solution when it comes to portable AC
units. Not everyone is living in a house they own: otherwise I agree

