Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Air Con: $1697 for an on/off switch

blog.hopefullyuseful.com

Post reply on HN
Print view View original

41–50 of 496 posts

Re: Air Con: $1697 for an on/off switch

#41

Post by ranebo »

kalleboo wrote: post #12
syntaxing wrote: post #3

I don’t quite get why snipping the data line on the PoE to USB fixed the connection issue. Is it because the USB has “two” data lines?

The "PoE"[0] board was also a USB device wired onto the pins for the single USB port on the board. USB is not a multidrop bus - if you directly wire two devices to a single USB port it will not work, you need an active USB hub. [0]quotes because looking at that FTDI chip though my bet is it's actually serial over Cat5...

I think it is some sort of serial comm over cat5. My only concern was getting the thing working again :) But if still interested here is a close up of the chip side of the POE connector: https://blog.hopefullyuseful.com/blog/advantage-air-ezone-ta...

Re: Air Con: $1697 for an on/off switch

#43

Post by pxx »

biggc wrote: post #38
SOLAR_FIELDS wrote: post #28

Earlier quoted context omitted.

I highly recommend people who live in hot environments to keep a spare capacitor on hand. Even if you know how to fix it, if the AC dies when your local HVAC supply store is closed (eg not between 7am-7pm Monday through Saturday usually) you’re either stuck paying out the nose to a contractor who has one on hand during emergency hours or you’re sweating it out waiting for the store to open. While they are readily ava…

How big can these capacitors be? Does replacing it require any safety precautions besides turning off the power?

the capacitors are connected across the motor windings and are there essentially as a way to shift the phase of the current waveform. note that this is a two-phase power special; you don't need start or run capacitors if you're using 3-phase power (uncommon in North American residential settings, but YMMV worldwide)

when power is disconnected they are not charged at all. it's not like the capacitors you might find in a CRT

Re: Air Con: $1697 for an on/off switch

#44

Post by SOLAR_FIELDS »

Nursie wrote: post #39
cbanek wrote: post #17

This is when smart gets stupid. I'm a bit worried about this with my nest and other smart devices, but even with normal air conditioners there are a few stupid simple problems that will cost you hundreds of dollars! A couple of weeks ago my AC blower fan stopped working, the compressor would run. I went up and found out that the capacitor was bad, and took a picture of it, buying a replacement. Took about 15 minutes…

The great thing about Australia is that that is probably illegal here. We've got some pretty fucked up protectionist rules about what you can and can't do in/to your own home. It's nuts. Now, nobody is actually watching most of the time, so you're usually fine, but it's as stupid as being illegal to replace a tap or existing light fitting. Every so often state governments review the rules and get swamped by trade ass…

Reminds me how, in USA, it’s the only civilized nation I’ve been to where you must have a prescription to purchase contacts and glasses. Everywhere else I’ve been will just sell you whatever magnification you need at the pharmacy.

Obviously there is some acceptable line here, but I think the States handles this decently well enough. In Austin where I live you can get what is called a “homeowners permit” in a lot of cases. Meaning the city will come look at your work and as long as it’s up to code you get a legal permit just like a contractor would get (https://www.austintexas.gov/page/homeowners-permit). You can only do this to your own home so it’s not a shortcut to running a chuck in a truck business without a license.

Re: Air Con: $1697 for an on/off switch

#45

Post by ranebo »

redact207 wrote: post #6

I love that this man resurrected his blog after 10 years just to write this. Anger and spite are strong motivators.

You have no idea how true this is :). I had to upgrade everything, the old site didn't even have SSL. But this annoyed me so much I wanted others to know how to fix it.

Re: Air Con: $1697 for an on/off switch

#46

Post by [deleted] »

biggc wrote: post #38
SOLAR_FIELDS wrote: post #28

Earlier quoted context omitted.

I highly recommend people who live in hot environments to keep a spare capacitor on hand. Even if you know how to fix it, if the AC dies when your local HVAC supply store is closed (eg not between 7am-7pm Monday through Saturday usually) you’re either stuck paying out the nose to a contractor who has one on hand during emergency hours or you’re sweating it out waiting for the store to open. While they are readily ava…

How big can these capacitors be? Does replacing it require any safety precautions besides turning off the power?

[deleted]

Re: Air Con: $1697 for an on/off switch

#48

Post by teslabox »

SOLAR_FIELDS wrote: post #28
cbanek wrote: post #17

This is when smart gets stupid. I'm a bit worried about this with my nest and other smart devices, but even with normal air conditioners there are a few stupid simple problems that will cost you hundreds of dollars! A couple of weeks ago my AC blower fan stopped working, the compressor would run. I went up and found out that the capacitor was bad, and took a picture of it, buying a replacement. Took about 15 minutes…

I highly recommend people who live in hot environments to keep a spare capacitor on hand. Even if you know how to fix it, if the AC dies when your local HVAC supply store is closed (eg not between 7am-7pm Monday through Saturday usually) you’re either stuck paying out the nose to a contractor who has one on hand during emergency hours or you’re sweating it out waiting for the store to open. While they are readily ava…

> But HVAC supply shops will sell them to you, you don’t need to be licensed or anything to buy them.

My local HVAC supplier doesn't sell to non-licensed people. I think they don't like dealing with returns from people who don't know what they're doing. I needed a 24vac transformer once. My dad used the same HVAC company for his office for a long time, they still remembered him, and had the part I needed in stock.

My brother's capacitor went out, but we found the part he needed at a local Grainger branch. https://www.grainger.com/category/motors/motor-capacitors

Two summers ago my AC didn't sound right. IIRC the outside unit was clicking on and off. I pulled the breaker. Eventually I decided the problem was with the contactor (a switch controlled by 24vac). I took pictures of where the wires were connected and pulled the contactor. For no particular reason I started taking the old contactor apart, and found a cricket in the middle. I removed the bug, cleaned out the cricket residue, put the contactor back together, and returned it to the outside unit. My AC system resumed working perfectly. https://en.wikipedia.org/wiki/Contactor

Re: Air Con: $1697 for an on/off switch

#49

Post by SOLAR_FIELDS »

biggc wrote: post #38
SOLAR_FIELDS wrote: post #28

Earlier quoted context omitted.

I highly recommend people who live in hot environments to keep a spare capacitor on hand. Even if you know how to fix it, if the AC dies when your local HVAC supply store is closed (eg not between 7am-7pm Monday through Saturday usually) you’re either stuck paying out the nose to a contractor who has one on hand during emergency hours or you’re sweating it out waiting for the store to open. While they are readily ava…

How big can these capacitors be? Does replacing it require any safety precautions besides turning off the power?

The capacitors size themselves are small. They slightly vary but are almost always the size of a medium Red Bull can. They are sized to your unit though so you can’t just buy one without looking at the specs and expect it to work. But the specs are printed on the side of the can and if not can be derived from the specs on the unit itself.

As far as their danger there really isn’t any beyond getting shocked from dealing with live wires. Technically they can retain a bit of a charge so I’ve seen recommendations to wait X amount of time before touching them with your bare hands or to discharge it by touching it with an insulated screwdriver to discharge it but the risk is pretty low. Once the power is off (either at the breaker or via the disconnect at the condenser unit, power only goes in one way to those things so if you turn it off in one place there’s no way you’ll get a zap) it’s a soda can with 3 wires going into it. You just disconnect the 3 wires from the old soda can, remove it, replace and connect the new one. Not that much harder than changing a light bulb.

Re: Air Con: $1697 for an on/off switch

#50

Post by boardwaalk »

0cf8612b2e1e wrote: post #16

Reaffirming my belief that I want nothing “smart” controlling critical infrastructure in my home. What if it were dead of winter, would he have been able to control the heat?

There are thermostats, among other things, that use standard protocols and still work in a “dumb” way if not connected. You just need to do some homework.
Post reply on HN