I honestly wouldn't know how to work in this summer without that portable AC of mine... Yes, it costs power. But I only run it when I'm working, only in the office, only to a 25°C target, and it's the most climate friendly option I could find back in 2019 too (R290).

Really happy about an efficiency improvement today! Took the Flir One & scanned my setup for heat creep. Turns out the outlet is fairly well isolated, but the hose turned out to be leaking some air & also radiating heat. Duct tape + blanket ftw! Achieving 10+°C difference now!

And thanks to everyone who pushed me in the direction of a dual hose conversion again. I'm still not convinced I can make that work in my room & window layout, but considering the heat & energy prices these days I'm going to give it my hardest try. Wish me luck.

Definitely consider this (accidental*) dip to 23.4°C with an outside temperature at 34.5°C (measured on the north facing front) my biggest win of today! 😊

* Why accidental? Too low target temperature set 😬 Doesn't exclusively happen with 3d printers 😅

New backplate for the AC to convert it to a dual hose setup, all parts printed over the last few days and now epoxying together. Thankfully did not have to design this myself, someone already did and shared 👍😊 thingiverse.com/thing:5421906

Just hope it really fits 😅

After just now disassembling the backplate and comparing things directly I'm very optimistic that it will indeed fit 😊

And the new window adapter plate is making progress, almost done, just needs some sealing on top and a coat of varnish 👍


@foosel Stupid question maybe, but why two ducts? Isn't it "just" heat exhaust? Wouldn't one duct be enough for it?
Pardon me please, I don't know much about A/Cs except they are basically heat-exchangers 🙂

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@blindcoder Not a stupid question at all! This article sums it up better than I ever could: woolie.co.uk/article/convert-a

But to give a quick tldr, single hose units use inside air for the heat exchange and then pump it outside. That creates a pressure differential in the room that causes hot air from outside of it to be sucked into it. Dual hose setups separate the outside air loop from the inside air loop, which increases efficiency by a lot.

@foosel @blindcoder I wonder why most ACs are still produced without this option. It's not only stupid. Sometimes it's also dangergous and forbidden (for example in cases you are using gas heaters) because of lowering the pressure in the apartment making it possible to suck back exhaust gases.

@foosel @blindcoder did this kind of mod 2 years ago (with plywood and duct tape on the AC, hoses up converted to 150mm, 2 airduct silencers and a 50W support ductfan, including a full size "window replacement" from polyresin fibre)
still working great.
against the hot outlet and 35 degrees inlet, stone fibre/whool with aluminum coating helps a lot better than any household fabrics.

@foosel Wow, that's some new information to keep in mind, thank you!
Seems my unit can not be converted non-destructively as the entire backplate (including the control panel) is a single piece. Next time I buy one I'll definately check if it's convertible, or comes with two hoses from the start!

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