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Turning a dumb AC unit smart (without losing my security deposit)

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Re: Turning a dumb AC unit smart (without losing my security deposit)

#31

Post by a-dub »

EvanAnderson wrote: post #14
a-dub wrote: post #12

that's a fun project. i'd be a little concerned about the servos failing to fully switch the switches or placing wear on them, maybe a dangerous failure mode where it is switched into and left in an in-between state unattended that could lead to a fire hazard. you can buy smart outlets with the correct connector, just look for 20A versions. (honeywell, at a minimum, sells one). https://prod-edam.honeywell.com/content…

The lack of feedback from the AC unit makes using a switched outlet potentially problematic. You really need to know the state of the compressor cycling before you go mucking with turning it on and off. (At least this was the case with the refrigeration compressors I am familiar with from my youth.) A current sensor could provide feedback but that goes beyond a regular smart switch.

i don't think that's true. i still have a thinkeco ac modlet that coned sent me years ago as part of some kind of "make your ac smart" promotion.

if you turn those knobs to the off position while the compressor is running, does it actually go into some kind of orderly shutdown or does it abruptly cut power to the compressor?

Re: Turning a dumb AC unit smart (without losing my security deposit)

#33

Post by Moto7451 »

Maybe not as fun but my sun room window unit is controlled by an off the shelf $20 thermostat designed for Air Conditioners. It’s the LUX Win 100 and is date/time programmable and features a compressor lockout so it doesn’t burn out your window unit by short cycling.

If you have a favorite smart thermostat you could also wire up a receptacle with a contactor between it and a cord and a 24v AC transformer wired to the line side. This would make your window unit controllable just like a central air conditioner.

Re: Turning a dumb AC unit smart (without losing my security deposit)

#34

Post by chpatrick »

andix wrote: post #23

OT: I'm looking for some way to control my AC via Infrared. I have a few pretty standard AC units with IR remotes. The ones with a display on it, that just transmit all the settings on the remote via IR on every button press. Some device I can mount in proximity, that controls the AC, but preferably also has a temperature and humidity sensor included.

Some ACs have UART interfaces inside that can be fairly easily hooked up to an esp32.

You could also buy an IR transmitter module from AliExpress and add a temperature/humidity sensor chip on I2C like an SHT41.

Re: Turning a dumb AC unit smart (without losing my security deposit)

#35

Post by drdexebtjl »

Liftyee wrote: post #20

I don't get how so many large buildings in NYC and Beijing (two cities that I've personally visited) use independent little AC units like the PTAC or minisplit types. A couple per apartment, peppered over the outer walls. Engineers intuition says surely a large central unit would be more efficient and effective. Is it because of personal ownership reasons? Counterintuitive physics? Heat dissipation limitations on the…

I had the option to buy a “central” unit or several mini splits for my apartment. I chose several mini splits. The main reason is that they can fail independently, so I’m not stuck in an apartment that is hot everywhere.

But I think the main reason is that in places without central AC, people tend to want to incrementally upgrade. For example, you might get a mini split just for your bedroom, because that’s the room you require the most comfort during the hot days. Then when you start getting used to the comfort of the AC in the bedroom, you’ll want one in the living room. And so on.

Re: Turning a dumb AC unit smart (without losing my security deposit)

#36

Post by arikrak »

post_break wrote: post #8

Assuming running a dual hose inverter portable AC isn't against the lease agreement it would probably pay for itself based on the power usage. Pretty neat hack regardless.

Portable ACs are generally less efficient than regular window ACs and PTAC units since the compressor is inside the room.

Re: Turning a dumb AC unit smart (without losing my security deposit)

#37

Post by ghaff »

EvanAnderson wrote: post #13

The "couple a stepper motor to a shaft" API is so much better than any "smart" appliance API. Speaking more seriously, I wish classes of appliances would expose some simple analog and digital interface pins in a standardized configuration to let users choose whatever automation or monitoring hardware they want. HVAC equipment does this with standardized thermostat terminals. I'd love to see that on other types of app…

When I had a kitchen fire, I told my electrician "no smart stuff" and he was happy to go along. (I had very little previously.) He did simplify and updated my electrical panel and switches which sort of accreted over time.

Re: Turning a dumb AC unit smart (without losing my security deposit)

#38

Post by bob1029 »

a-dub wrote: post #31
EvanAnderson wrote: post #14

Earlier quoted context omitted.

The lack of feedback from the AC unit makes using a switched outlet potentially problematic. You really need to know the state of the compressor cycling before you go mucking with turning it on and off. (At least this was the case with the refrigeration compressors I am familiar with from my youth.) A current sensor could provide feedback but that goes beyond a regular smart switch.

i don't think that's true. i still have a thinkeco ac modlet that coned sent me years ago as part of some kind of "make your ac smart" promotion. if you turn those knobs to the off position while the compressor is running, does it actually go into some kind of orderly shutdown or does it abruptly cut power to the compressor?

The wiring diagram for this article seems to reflect it would be a hard shutdown. Most HVAC systems I have interacted with have zero problems with a sudden power loss. The only potential issue is bringing the compressor back up too quickly on the other side. You could easily control for this if you were switching the whole unit using software.

Re: Turning a dumb AC unit smart (without losing my security deposit)

#39

Post by andix »

mardef wrote: post #28
andix wrote: post #23

OT: I'm looking for some way to control my AC via Infrared. I have a few pretty standard AC units with IR remotes. The ones with a display on it, that just transmit all the settings on the remote via IR on every button press. Some device I can mount in proximity, that controls the AC, but preferably also has a temperature and humidity sensor included.

I use http://getmysa.com for this. they have their own app and scheduling, but i just automate mine via homeassistant

This doesn't look like it can control the AC unit via infrared. How did you solve that part?

Re: Turning a dumb AC unit smart (without losing my security deposit)

#40

Post by ghaff »

Guvante wrote: post #25
lstodd wrote: post #19

Earlier quoted context omitted.

It always blows my mind why those rich people even bother with TVs. I'm not rich by any measure, but still I can afford a projector, a screen and a couple KRK monitors.

Multi use rooms require TVs. Projectors cannot handle ambient light without being a fire hazard.

>Multi use rooms require TVs

That seems an overstatement. I now have one in my entire house (don't have kids).

There's a fairly large TV panel on one wall in basically a sitting room. Otherwise I just use a computer. A relative basically has TVs in every room. I guess it maybe made sense when he was rebuilding anyway but it still seems excessive to me who might sit down to watch a movie or show but doesn't have live TV.

But, then, I don't have AC either in Massachusetts.

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