Comment on I've been using this simple trick to keep cool in the heat wave (UK)

• Kazumara@discuss.tchncs.de ⁨4⁩ ⁨days⁩ ago

  while preventing outside air from getting in

  If that worked you’d slowly turn your dwelling into a vacuum chamber :-)

  The same volume of air will enter your home in one way or the other, the important bit is that it’s cooler than the exhausted air. In particular you don’t want the hot exhaust to recirculate back in.

  Ideally you’d get medium warm air from another room into yours, and warm outside air into an unoccupied room.

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  • tormeh@discuss.tchncs.de ⁨4⁩ ⁨days⁩ ago

    Thank you. I thought I was insane because surely mobile units would have two tubes if they really needed them. Then I got one with a single tube (the only ones available) and found out that no, I am sane and these units work really badly.

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    • Zwiebel@feddit.org ⁨3⁩ ⁨days⁩ ago

      That’s why the earlier comment mentioned the portable minisplit, it doesn’t have this weakness

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    • ByteJunk@lemmy.world ⁨4⁩ ⁨days⁩ ago

      I find mine works fairly well, it’s a 12k BTU unit.

      It has one exhaust duct. It pulls in warm air from the room it’s in, cools part of it and pushes it back into the room, the rest is used to cool the condenser and that hot air is sent outside through the duct.

      It does have another tube, but it’s a small hose to drain the water from condensed humidity.

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      • elucubra@sopuli.xyz ⁨2⁩ ⁨days⁩ ago

        It pulls in warm air from the room it’s in

        Until the room is cooled enough that you are using the air you have paid to cool, to cool the evaporator. Portables are shit.

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  • EndlessNightmare@reddthat.com ⁨3⁩ ⁨days⁩ ago

    Dual-hose portable ACs avoid the vacuum problem. You just need to have good sealing around the intake and exhaust hoses.

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    • Kazumara@discuss.tchncs.de ⁨3⁩ ⁨days⁩ ago

      Oh I haven’t seen one of those yet, that does sound like an improvement.

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    • starik@lemmy.today ⁨3⁩ ⁨days⁩ ago

      So it creates positive pressure in the house?

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      • EndlessNightmare@reddthat.com ⁨3⁩ ⁨days⁩ ago

        The air that is brought in from outside via the intake hose is the same air that is heated and then ejected through the exhaust hose.

        In theory, it shouldn’t cause a change in pressure.

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  • de_lancre@lemmy.world ⁨4⁩ ⁨days⁩ ago

    Yep, main problem with those portable units is that their efficiency is pretty bad. They does work and cool the room, but amount of energy that needs to be spent, plus the fact that you need to somehow restrict airflow to not be sucked right back in - makes them a horrendous option. Better than nothing I guess.

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  • ByteJunk@lemmy.world ⁨4⁩ ⁨days⁩ ago

    Well yes, I meant preventing that hot air from circling back inside through the window, since these usually come with a kit to fit into the window, but aren’t particularly airtight.

    Also I’m genuinely amazed at how fast that thing fills a bucket with water from the condensation, it’s ridiculous. I live near the sea so 70%+ is normal, but seeing it was still surprising.

    I have mine in the living room and it pulls in air from the rest of the house, air filters in from many different places.

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• meekah@discuss.tchncs.de ⁨4⁩ ⁨days⁩ ago

  Yeah those are much more common and way cheaper, but also much less efficient.

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• elucubra@sopuli.xyz ⁨2⁩ ⁨days⁩ ago

  Portables are hot garbage. Get a proper air source wall split. Cheap and immensly cheaper as a heat source that anything you use right now.

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