I have been advised to steer clear of "evaporative coolers". While some retailers sell these in NZ, they are unsuitable for our humid climate. Really they are designed to work in places like the Australian outback or Arizona where the air is drier. 

Portable AC units should have a tube out the back that you vent to the outside, like a dryer. This will give you that ice-cold breeze.

Points to remember these units will generate condensate, i.e. water.. That needs to go somewhere, either into a tank or through a pipe somewhere; if it's a tank, that will need emptying and will stop the unit working when it's full.

Compare outputs typically measured in KW, and ensure your path to the outside is as short as possible. If a long length is unavoidable, I would try to insulate the pipe outdoors with towels, etc. 

Evaporative Cooling Units

If it doesn't have a tube it is most likely an evaporative cooling unit, which requires a phase change, liquid to gas, to work. Which, depending on the conditions, doesn't always make you better off.

Will an evaporative unit work today?

Take a bowl, half-fill it with water, then top up with ice. Place a fan so the air stream is moving over the top of the water. If the resulting breeze feels cool, then it will work.

They don't always work as if the air is already humid. It's harder for water to evaporate into the air; this evaporation process cools the air temperature.

For some science fun, repeat the water and ice bowl trick, put some salt in it, along with a room temperature can of drink.. 5 minutes later, you'll have an ice cold drink. (Salt water has a much lower freezing temp, so it will melt the ice, the phase change from ice to water will create cooling energy which has to go somewhere, and that will be your drink)
 

Not only that, but if it is a single hose model, any hot air it exhausts out the window will have to be replaced - by drawing in hot air from the rest of the house/outside :-(

Noisy is the norm for these. To get that much heat out thru a tiny 100mm duct, they have to have a screaming loud fan. All that air is replaced thru leakage coming in thru other places. When I had one it made the rest of the house noticeably warmer and you could see curtains in the other parts of the house move when it kicked on as the air started coming in.

Even running constantly it was not able to get inside down to 20 when outside was 32, and sucked 1400 watts in the process.

A proper 3.5kw aircon in the same room will get it to 18 quietly, easily and be throttling right down, and uses about 800 watts at its worst.

IMO don't bother with the portable. We cant get the good portable split systems here because of aircon installation laws, so we just have the box with an exhaust hose crap.

Perhaps consider a window box aircon, as those have the guts hanging outside and do not require air intake like the box with hose types, but the few I have seen have been too wide for any normal window I have seen.

If you only happened to own an EV, all your problems could be solved! 

(Source: NZ Model 3 group)

Heh, that is some serious what the frank!

networkn:

 

Heh, that is some serious what the frank!

 

Yeah, as you'd expect he's faced a bit of push-back, but is pretty defensive about it!

"This is more about a zero dollar solution, for a short period of time, just for a few afternoons during summer, not worth me spending any extra dollars to install an AC.

I'll be kind and say his response is in line with my expectations. 

pih: The two issues with portable units is that they are inefficient at exchanging heat and they create negative pressure indoors. In other words, by running one, you'll be using some of the cooled air to remove heat from the heat exchanger, then pump it outside, creating low pressure inside. This then draws warm, moist outdoor air in, reducing efficiency significantly. Basically the only cool place to be with a portable unit on a hot day is right in front of the vent. If there's any possible way to put in a split system instead, do it, it's at least twice as efficient.

Unfortunately, at this stage there isn't an option for that.

There are two hose models that eliminate that issue. Technology Connections made a video about the subject a few years back.

2kadmin:

 

Evaporative Cooling Units

 

If it doesn't have a tube it is most likely an evaporative cooling unit, which requires a phase change, liquid to gas, to work. Which, depending on the conditions, doesn't always make you better off.

Will an evaporative unit work today?

Take a bowl, half-fill it with water, then top up with ice. Place a fan so the air stream is moving over the top of the water. If the resulting breeze feels cool, then it will work.

They don't always work as if the air is already humid. It's harder for water to evaporate into the air; this evaporation process cools the air temperature.
 

 

its not that they don't work. even in humid climate they will work a bit. the big thing is it makes the house even more humid. humidity is a big factor in comfort, so by increasing the humidity it feel even worse than it really is. which is why 32c in auckland is a heat wave and 32c in chch is just a pleasant day. 

as mentioned, they are best suited to dry areas where increasing the humidity is a good thing. 

tweake:

 

its not that they don't work. even in humid climate they will work a bit. the big thing is it makes the house even more humid. humidity is a big factor in comfort, so by increasing the humidity it feel even worse than it really is. which is why 32c in auckland is a heat wave and 32c in chch is just a pleasant day. 

 

as mentioned, they are best suited to dry areas where increasing the humidity is a good thing. 

 

Technology Connections did a video on them as well if anyone's interested in more info.

Also, I dispute the idea that 32 °C could be comfortable at any humidity level. 🥵

I got a Vostok 3.5kW from Dick Smith/Kogan in preparation for summer and it's glorious. I'm pretty sure it's a relatively generic one (i.e you'll probably find one with a different brand) but it takes my office from 29 degrees inside to 22 degrees. That, and a sliding door vent from Amazon and it's perfect.

It's noisy, but any portable unit will be. Once it does the initial cool, it quietens down quite a bit.