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What else have I been up to... I fixed a friend's air conditioner yesterday. It was running the compressor any time it was plugged in, so I figured a stuck relay and yeah, it was a stuck relay. Gave it a good smack and that got it to behave for a few cycles, ended up pulling the board and replacing the relay with a new one.

Swapping a five dollar part clawed back three hundred bucks from The Capitalists!

· · SubwayTooter · 1 · 9 · 22

It was complicated a tad 'cause Lucky-bloody-Goldstar went and poured glue all over the back of the board, so I had to cut/chip/melt away some gunk before I could get to the solder joints.

Life's Good, huh.

Anyway this is the kind of repair where it makes sense for this to be your first attempt at board work - it's a cheap part on an unobtainium board and your only other option is buy a whole new expensive unit.

If you were starting from absolute zero, buying a soldering/vacuum desoldering station, you'd still be quids in over buying a new air conditioner.

There's a certain freedom in being forced into the "Heck, let's give it a go" option. It gives you license to be just reckless enough to try.

People are often afraid of fixing things because they're worried that they might make it worse.

People Who Fix Things often gain their confidence through fixing things that are broken so thoroughly as to be completely dead or useless, and figuring "heck, it's already knackered, it's not as though I COULD make it any worse."

Finding and swapping out the $2 part that stops a $500 machine from working is always a hell of a rush. That's $498 in your or a loved one's back pocket. It never gets old!

I've never fixed an air conditioner before, but there are universal rules of fixing electrical machine that apply really broadly.

In this case the compressor was running when it shouldn't be. A computer (which usually run on very low current and very low voltage) has to turn the compressor (which runs on mains current and draws a whole bunch of amps) on and off, so it's gotta use something in between the computer and the compressor like a relay or a power transistor...

...because if you hooked one leg of the computer chip up to a compressor and tried to drive it, the computer chip would just burn right up with all the current.

Electrons have mass and a lot of them can't fit through a tiny conductor - this is so important in Finding The Broken Bit and *nobody tells you this.* Big current needs components that are physically big.

If someone at some point in your life tells you that *electrons are real and have mass so big current needs physically big components to fit all the electrons through,* and you know (as most of us do) that air conditioners drive up your electricity bill a lot more than just running a fan, then you don't need to know any secrets, you can *determine* that the bits on the control board associated with the compressor are gonna be the big chonk units.

We live under capitalism and the machine's broke and big current takes big components and big components cost more money than little components, so we can determine that Lucky Friggin' Goldstar cheaped out on the big chonkers, so it's probably the biggest chonker that done burned up.

All this is before you even pull out the multimeter! I would've done just that but I heard a click when I poked the big chonker so I didn't bother.

Another fixing-things thing that's obvious to People Who Fix Things but nobody tells you: most components and nearly every chip has a number written on it and if you pop that number into any search engine you'll get a datasheet, which is a PDF that tells you everything there is to know about the thing and what it does and how it should behave and how to wire it up and some things it might be used for.

So I just popped that number into eBay and got two for a tenner

@ifixcoinops That's where hardware hackers might be born too, like in my case where I go at some broken device, manage to destroy the broken part further, and decide to just replace it with something cooler

@ifixcoinops Was there any reason for the glue backing other than making it more difficult to self-repair?

@whami Well if they'd done both sides I'd assume to avoid moisture intrusion, but they didn't so ㄟ(ツ)ㄏ

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