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Cake day: July 15th, 2023

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  • What you might deal with is heat soak if the fans can’t move enough air over the condenser core. But modern vehicles are immensely more efficient than even 10 year old vehicles.

    You’re point?

    They’re not designed to idle for extended periods, and doing so puts strain on the systems. that the cars are “more efficient” doesn’t change that.

    the AC compressor isn’t a significant load, no. But it’ expects a certain engine RPM coming into it, and it’s designed at that. It’s significantly less when the engine is idling because that’s below it’s designed range. There’s a reason the manufacturers tell you not to idle your car for extended periods (mine says more than 10 minutes, my last one said 5.) and this is part of it.

    the increase in RPM modern cars do isn’t for the AC system. it’s to keep the engine from stalling and running smoothly… the compressor is still not designed to operate at that RPM.


  • However, disagree with the statement that a climate control system is not meant to be operated while idle. That is an old myth that I expect came from back when there was fewer electrical components in the car so not turning the ac /off/ before turning the vehicle off would risk damaging the cars electrical.

    that’s not actually a myth. The car is functionally not designed to be left on idle for extended periods. (Note, I’m saying extended periods. Warming/cooling your car at idle is normal. idling at a stop light is normal. Five minutes while waiting to pick some one up is normal. Leaving it to stay cool for 2 hours is outside that design window.)

    When an engine is idling, it’s turning at a lower RPM than when moving. of particular note here is that the alternator and AC compressor are both driven by the serpetine belt directly connected to the crankshaft. The lower RPM makes both less efficient. For the compressor, what this means is that the AC system is turning more slowly than it normally would, reducing the total amount of cooling. For the alternator; it produces less electricity and may cause the battery to be discharging. Depends on some things, including how hard the AC is having to work, etc.

    Further, because the car is not moving, there is less air moving around the engine compartment (or wherever the radiator for the engine and the AC is located.) This equates to higher operating temperatures for the engine, as well as yet more reduced ability for the AC system to remove excess heat from the cabin.

    just because an AC can be run at idle for extended periods doesn’t mean it’s designed to, and doing so, especially on old or poorly maintained systems, in excessive heat, is likely to cause it to crap out where it wouldn’t have normally. Is it a particularly high probability? Not really. Is it still too high considering it’s a life-safety system? fucking absolutely.









  • FuglyDuck@lemmy.worldtoScience Memes@mander.xyzwolf spiders
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    4 days ago

    So, true spiders digest their food externally by injecting the venom. They then slurp it up. So the answer to that is “Yes”. Some true spiders may also eat the more solid bits, but that’s in addition to. but again, many- most- spiders are essentially harmless to humans.

    harvestmen (daddy long legs) are not venomous and lack the mouth-parts necessary for injection, but they’re not true spiders.



  • FuglyDuck@lemmy.worldtoScience Memes@mander.xyzwolf spiders
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    4 days ago

    To add to what nougat said, because that’s very much the appropriate answer…

    All spiders are in fact venomous- it’s part of how they feed. Many species, the venom is not harmful to humans, or only very weakly so. (Wolf spiders qualify as “very weakly so”)

    That said, you try keeping a reasonable head when you suddenly come eyeball-to-eyeball with a wolf spiders qualify and her kids.




  • FuglyDuck@lemmy.worldtoMildly Infuriating@lemmy.world(Not so)Smartphone
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    7 days ago

    Because apple only maintains phones on an individual level?

    And probably literally everyone who writes apps for iOS, as they would now need to account for everyone’s potential behavior.

    It’s not “only”. Especially if you had to account for every possible variation in hardware. It’s more complexity and that means more opportunity for bugs.