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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

#11

Post by porknubbins »

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.

Isn’t this is only true with central air though? Most other types of ac are not full climate solutions to leave running all the time and need some manual control.

At least that’s how I use the mini split in my garage. I have to remember to give it 15-20 minutes headstart before I use the garage or will be really hot.

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

#12

Post by skolos »

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.

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

#13

Post by HeavenFox »

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…

FYI this kind of thermostat is actually better. American style thermostat put your HVAC system in either on or off state (basically PWM), whereas this kind of communicating thermostat can tell the system what the temperature is, so they adjust power accordingly. I do wish they have standardized protocol though.

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

#14

Post by cgrin »

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.

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

#15

Post by burner420042 »

llsf wrote: post #6

Does anyone know if this could be used to "cap" the AC settings ? It could be useful in an airbnb place, where I want to limit the lowest (e.g. 18 degres Celsius) or hottest (e.g. 22 degres Celsius) the guest can set the AC.

To answer your question, yes you could certainly do that and override what ever the physical thermostat was set to. You could also set max hours per day (kWh)for usage or adjust for variable rate plans. As with anything you'd need to test.

Edit: Looking through the repo and the article I see nothing blocking you. You certainly won't break anything!

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

#16

Post by userbinator »

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.

You shouldn't need to change the temperature regardless of those things. My house remains at 68-72F basically all the time. Thermal cycling accelerates aging of materials.

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

#17

Post by llsf »

sippingabonedry wrote: post #7
llsf wrote: post #6

Does anyone know if this could be used to "cap" the AC settings ? It could be useful in an airbnb place, where I want to limit the lowest (e.g. 18 degres Celsius) or hottest (e.g. 22 degres Celsius) the guest can set the AC.

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 like it very cold.

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

#18

Post by sippingabonedry »

HeavenFox wrote: post #13
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…

FYI this kind of thermostat is actually better. American style thermostat put your HVAC system in either on or off state (basically PWM), whereas this kind of communicating thermostat can tell the system what the temperature is, so they adjust power accordingly. I do wish they have standardized protocol though.

Depends on your definition of better.

It's a tradeoff I'm willing to make for simple, open I/O. It's not PWM but rather a "call" for heat, cooling, or fan. If I'm refinishing the wall I can (and have) put in a $3 thermostat in its place so I don't destroy the $300 one with paint and dust.

It's also very easy to debug and repair, as I experienced on a day when the temperatures exceeded 100F and was able to execute an emergency repair myself.

If companies like Nest and Ecobee were not allowed to exist, we would all be stuck with the overwhelmingly universally overpriced, proprietary garbage the OEMs put out.

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

#19

Post by murderfs »

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…

Most new construction with heat pumps are going to use similar thermostats, both because of improved efficiency since the outside unit wants to know how much heating/cooling load is being requested, and more importantly, because builders are lazy and would rather use a battery-powered wireless option than run thermostat wires.

Off the top of my head, Mitsubishi, Rheem, Lennox, and Carrier all have similar default options, with converter boxes for retrofits to 24V controls.

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

#20

Post by llsf »

burner420042 wrote: post #15
llsf wrote: post #6

Does anyone know if this could be used to "cap" the AC settings ? It could be useful in an airbnb place, where I want to limit the lowest (e.g. 18 degres Celsius) or hottest (e.g. 22 degres Celsius) the guest can set the AC.

To answer your question, yes you could certainly do that and override what ever the physical thermostat was set to. You could also set max hours per day (kWh)for usage or adjust for variable rate plans. As with anything you'd need to test. Edit: Looking through the repo and the article I see nothing blocking you. You certainly won't break anything!

Thanks! I don't think I would need to do max hour per day.
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