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I added a non-wi-fi Mitsubishi AC to Home Assistant

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Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#61

Post by bluGill »

kotaKat wrote: post #54
bluGill wrote: post #51

Earlier quoted context omitted.

Until the kid uses the bathroom in the middle of the night and goes back to bed. Though the GP seems to not mind stale coffee so perhaps he won't care. Exceptions like the above make automations hard.

DR stands for "didn't realize"; the first time it happens you just run back to the drawing board and add some safety boundaries on it. So... just make sure the automation only becomes available from ~6 AM to 8 AM. ;)

Sure, but in home automation there was a whole lot of those didn't realize situations that you won't get right. In the one end I often go for the question, 'is it really worth the bother of trying to set this all up'?

In most cases, there's nothing wrong with the switch on the wall. I don't need a complex home automation. I do have Home Assistant. It isn't very useful. It's kind of nice to have a couple of lights on from dark until 9 p.m. but with the efficiency of modern LEDs, it's probably cheaper to just leave those lights on 24-7 than to leave my home assistant machine on 24-7.

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#62

Post by bob1029 »

gruez wrote: post #57
bob1029 wrote: post #30

Earlier quoted context omitted.

Single stage hvac systems tend to have better performance in the max capacity cooling cases (Texas) and last significantly longer than units that rely on non-linear electronic devices. The difference can be as extreme as 10+ years of service life. There are residential systems that were installed in the 80s and 90s that are still running fine today. The hermetically sealed scroll compressor is an engineering marvel.…

>Single stage hvac systems tend to have better performance in the max capacity cooling cases (Texas) and last significantly longer than units that rely on non-linear electronic devices. Why?

Inverter systems have more conversion losses than single stage. Most of the time, I definitely intend to run my system as hard as it can. There are only 4-5 weeks out of the year where variable speed would make a meaningful difference.

Semiconductors wear faster than copper wires and contactors and are much harder to replace. I can take a part from my neighbor's condensing unit and it would almost certainly work in mine. The make/model is largely irrelevant. I can go on Amazon, search "Start+Run Capacitor" and buy the first thing I find.

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#63

Post by [deleted] »

skolos wrote: post #12
userbinator wrote: post #10

My idea of HVAC is that it should be "set and forget", so "smart" is the polar opposite of what I want. The round Honeywell on the wall has been doing its job for the past few decades, and will likely last many more with only an occasional cleaning.

If you have same schedule every week, don't go on vacation, your kids don't have breaks, don't have seasons, then 'set and forget' dumb thermostat will work for you without any problems. For the rest of us we need some 'smartness' in our thermostats.

[deleted]

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#64

Post by acyou »

These mini split inverter units seem to be good for +/- 1 C, but the 2 C swing can feel quite substantial.

PID control seems to be lacking overall, the control laws seem to be more basic. In particular, my unit waits until temperature deviation from setpoint exceeds 1C before cycling on. If I want finer control, there are a few options I can think of: 1. Spoof the temperature, add a TEC , heater, cooler or something to the sensor on the remote 2. Manipulate the controller buttons, change the setpoint down or up by 0.5 degrees so the unit kicks on after a 0.5 degree change instead of a 1 degree change 3. Spoof the temperature sensor itself, hack into the wiring with some transistor based circuit 4. Hack into the actual unit, fully take over the compressor and fan control 5. Buy a better unit or off the shelf controller 6. Spoof the remote control, reverse engineer the IR communication temperature signal

This last option seems the least intrusive and cleanest, I see other people have done it, it's definitely a lot of work even with AI.

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#65

Post by dgacmu »

rcxdude wrote: post #38
userbinator wrote: post #34

Earlier quoted context omitted.

Power is cheaper than things failing earlier than they could have due to thermal cycling.

Do you have any citation for thermal cycling through the range of an AC inside a house affecting the failure rate of any household goods? Based on my experience this does not seem likely to be the case: thermal effects tend to be exponential or high powers of temperature, and most thermal cycling that people worry about is on the order of 100C or more. 10/20C of variation seems unlikely to be relevant. (There is a ca…

But with most houses, the AC will cycle on and off throughout the day anyway - raising the temp while you're gone will often result in less cycling. Especially if you also increase the hysteresis range while out. So you get a triple efficiency win, from better AC efficiency, less AC motor wear, and less heat loss to the outside.

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#66

Post by micromacrofoot »

cgrin wrote: post #14
akifbayram wrote: post #2

I’ve been working on a similar setup using the M5Stack NanoC6 and AtomS3 Lite, and put together a parts list and wiring guide on my site: https://serin-labs.com/parts.html . I also built a web flasher with firmware configured for those boards, so you can install directly from your browser without any fiddling or configuring. The ESPHome option uses the same echavet/MitsubishiCN105ESPHome project mentioned in the arti…

The Nano is fine to connect directly because it has diodes on the data pins but the S3 Lite needs a level shifter or it'll eventually stop communicating with the air handler.

yeah came here to say this, I have my mini splits set up on the S3 light with level shifters, not worth skipping because they'll end up failing on you - requires a little soldering but nothing complicated

wiring:

1. Mini split black (GND) → ATOM G

2. ATOM spare G → shifter GND (either row)

3. Mini split red (5V) → ATOM 5V

4. ATOM spare 5V → shifter HV ref

5. ATOM 3V3 → shifter LV ref

6. Mini split yellow → shifter HV1

7. Shifter LV1 → ATOM (G2 / GPIO2)

8. Mini split white → shifter HV2

9. Shifter LV2 → ATOM (G1 / GPIO1)

if the gpio ends up being reversed you can handle it in software

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#67

Post by DrammBA »

llsf wrote: post #17
sippingabonedry wrote: post #7

Earlier quoted context omitted.

If you controlled the AC temperature remotely it's a great red flag to never rent that Airbnb. Some people like it cold when they sleep.

I understand, and I could make it clear in the description that AC is capped at 18 degres C minimum (65F), so people who like it very cold could skip my airbnb. Some AC can go ridiculously low ( http://news.bbc.co.uk/2/hi/uk_news/england/3144803.stm ). I do not want to change the temperature remotely, I just want to not have the AC used to extremely cold temperature. I am fine to advertise it to weed of people who li…

> Some AC can go ridiculously low (http://news.bbc.co.uk/2/hi/uk_news/england/3144803.stm).

Did you just post a link to a 23 year old news article with no sources on an http-only site as supporting evidence that your airbnb unit's AC unit can go dangerously low?

You really think your guests will get frostbite if you don't do them the favor of limiting the AC temperature (with the unintended side-effect of saving you some money)?

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#68

Post by sethhochberg »

numpad0 wrote: post #37
sippingabonedry wrote: post #5

For anyone wondering why he would ever do this, it seems to be a type of hidden mini-split system used in euro-style shoebox flats, with a super-proprietary thermostat. Wi-Fi capability is an option at additional cost, but was not purchased. In the USA, wired thermostats tend to use standardized 24V wiring schemes, or 208V/240V for mains voltage heaters (electric heat, common on the west coast, especially in shitty a…

Is this "mini" split? This type of panels are pretty standard for office buildings in Japan. Usually networked into building management system somewhere. Most household mini splits come with an IR remote, and don't support these panels. Standalone third-party thermostats are rare.

People tend to mix the terms around a lot, but generally you'll see the manufacturers use "ducted split system" or "mini split", where mini splits are the self-contained wall or ceiling mounted units.

I live in an NYC apartment with a similar Mitsubishi ducted split system - very short run ductwork just because the apartment itself is small, but takes up way less space than traditional American-style air handlers, even the apartment sized ones. The entire air handler is suspended above my bathroom ceiling, in between the drywall and the slab above.

My system was originally installed with the 2-wire serial wall thermostat but I converted it to one of Mitsubishi's Redlink wireless units because I needed to relocate the thermostat. But since Redlink isn't wifi, and the Mitsubishi networked thermostats and cloud platform get pretty poor reviews... this project is super interesting to me.

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#69

Post by madaxe_again »

bluGill wrote: post #61
kotaKat wrote: post #54

Earlier quoted context omitted.

DR stands for "didn't realize"; the first time it happens you just run back to the drawing board and add some safety boundaries on it. So... just make sure the automation only becomes available from ~6 AM to 8 AM. ;)

Sure, but in home automation there was a whole lot of those didn't realize situations that you won't get right. In the one end I often go for the question, 'is it really worth the bother of trying to set this all up'? In most cases, there's nothing wrong with the switch on the wall. I don't need a complex home automation. I do have Home Assistant. It isn't very useful. It's kind of nice to have a couple of lights on…

I gate it exactly as the parent says - automation only runs between 0530 and 0800, and when we’re home.

I literally couldn’t do without HA - I live off-grid, and it manages everything from monitoring water tank levels & running pumps to a power grid distributed over three independent and geographically distributed battery banks. Monitors for anomalies and tells me what is acting up - for instance today I got sent on a mission to find out why an array of PV was underproducing by 33%. Wouldn’t have noticed until it started having energy budget impacts otherwise. Makes decisions on whether today is a passive cooling/heating day or whether we have the energy budget to run climate control, when windows should be opened/closed to maximise efficiency, which blinds to close when depending on where the sun is to prevent or encourage passive solar gain, when to run the partially pumped storage hydro and in which direction, when to pull the pin on the deluge system and where if it’s set to wildfire mode. It has literally saved the house - not our lives, as we’d already evac’d and left it in charge of firefighting.

Stuff like the coffee machine and opening the blinds in the morning are just easy quality of life improvements, something less to have to manage manually, as my days are full enough that removing any point of friction is useful.

And yeah, I’ll take slightly stale coffee now over fresh coffee in ten minutes.

Re: I added a non-wi-fi Mitsubishi AC to Home Assistant

#70

Post by hattmall »

If anyone is looking for something similar it's worth looking into A somewhat less complex solution that preserves all functionality. Use the IR receiver plus a broadlink IR Hub. You can meet all the goals here, run it all locally the only downside is no 2 way communication. So if you do change the thermostat via the wall it won't be reflected in your app.
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