[HN Gopher] My Dream Thermostat
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My Dream Thermostat
Author : leontrolski
Score : 38 points
Date : 2025-05-06 22:11 UTC (50 minutes ago)
(HTM) web link (leontrolski.github.io)
(TXT) w3m dump (leontrolski.github.io)
| Animats wrote:
| 15 buttons?
| wpm wrote:
| I count 13, plus two 2-pos toggle switches.
|
| Either this or some awful tap tap tap modal interface.
| pphysch wrote:
| and 7 displays, though probably could get down to 3 without
| much compromise.
| vessenes wrote:
| I think you want Home Assistant. Now we ask, which thermostats
| let Home Assistant program them without cloud connectivity? I
| have no idea, but last time I looked, it was a rabbit hole.
| amadeusw wrote:
| ecobee works locally (without its cloud services) through Apple
| HomeKit.
| noduerme wrote:
| I have an ecobee. Quite nice and easy to program on the panel
| itself if you choose not to connect it to your wifi at all.
|
| One oddity with my ecobee - if it's not connected to wifi,
| the clock runs fast. Sometimes gaining a whole minute every
| few days.
| chipsa wrote:
| Cheap oscillator because they expect it to be network
| connected and be corrected by NTP. Why put in a good clock
| when a cheap one will do?
| broknbottle wrote:
| Honeywell T6 Pro
|
| https://www.amazon.com/Honeywell-Intrusion-TH6320ZW2003/dp/B...
| Jtsummers wrote:
| You can get something like that, though not that precise layout.
| I had one like that for years with a better interface than your
| sketch (until I forgot to take it with me from an apartment). It
| wasn't even "smart" (in the current internet-connected sense, I
| think it was still labeled as "smart" at the time since it was
| programmable).
| atonse wrote:
| Honestly this is what most of us want.
|
| I feel that while Nest changed the whole scene, it never lived up
| to its "smart" thermostat promise.
|
| And the schedule editor is way too cumbersome. Something like the
| above is what most people would use.
| sokoloff wrote:
| The schedule editor in the Nest App is "way too cumbersome"? I
| found it one of the most intuitive and just flexible enough
| editors of the various ones I tried (a relative judgment, and
| it was well past good enough in absolute terms).
| Raed667 wrote:
| Yeah that won't work for me, here are some missing features:
|
| - I want a button to make it a little colder for a period of
| 30-45 minutes
|
| - I want a toggle to alternate for days where I WFH
|
| - I want a 3rd time range: noon to 2PM
| bob1029 wrote:
| This is my favorite one so far:
|
| https://www.honeywellhome.com/us/en/products/air/thermostats...
| barnas2 wrote:
| You could easily make that. Thermostats are _very_ simple
| concepts. Basic A /C systems are 4 wires. Power, heat, cool, fan.
| If you want to cool the house, you connect power to "cool" and
| "fan". For heat, connect "heat" and "fan". If you just want to
| move air, then just connect the fan. Throw in some hysteresis so
| you don't short-cycle the compressor. With a raspberry pi, temp
| sensor, screen, and a relay block (the voltages are too high for
| a pi), you can probably build this in an afternoon/weekend.
|
| If you have heat pumps or a multiple zone system, or a few other
| things they can get more complex, but they still aren't super
| complicated.
| bityard wrote:
| Yes! On my long list of things to do when I get the elusive
| "round tuit" is to build an open-source touchscreen thermostat
| using cheap ubiquitous off-the-shelf parts. Probably something
| like a CYD (cheap yellow display, as they are known), an ESP32
| or RP3020, a good temp sensor, and some relays. The goal is to
| make it 100% compatible with Home Assistant as well as offer
| its own API and web interface to the local network. 3D print
| your case of choice.
|
| I have run across a few open source thermostats, but either
| they are some hobbyist's one-off project, or they are geared
| toward very different systems from the common North American
| forced-air furnace and whole-house AC unit combo.
|
| Before the but-what-about-ers start brigading in, yes it is
| possible to make this system safe against engineering or
| software defects. They make analog non-adjustable temperature
| sensors that "trip" below a certain temperature, you wire one
| in parallel with your heat wires near the furnace and you house
| will never go below freezing. (Very common in rentals.) If
| you're concerned about over-heating, add another temp sensor
| and relay and put it in series. Put time-out timers on every
| function. Have alerts sent to your phone. Add a SIM card and
| modem if you don't trust your wifi. And so on, tastefully
| adjusted to your own personal level of paranoia.
| behnamoh wrote:
| Am I the only one who naively clicked on all the buttons hoping
| to see them flick? :)
| ignorantguy wrote:
| I did the same thing!!
| burnte wrote:
| Nest Thermostats have done this for over a decade. There are lots
| of other brands, too.
| DaiPlusPlus wrote:
| The post isn't about what Nest doesn't do - it's about smart-
| thermostats like Nest having straightforward UIs and excessive
| amounts of IoT bollocks and seemingly arbitrary user-
| restrictions (e.g. Nest won't let you get raw access to
| temperature history data directly from the device: you can only
| get it via flashy GUIs in Google's apps (no API or CSV access)
| and even crazier: only for 10 days. Google is meant to be the
| king of Big Data but storing historical thermostat temperature
| data is too much for google, it seems...).
| GaggiX wrote:
| This could be a nice project to diy.
| vortico wrote:
| I want to specify heat, cool, or auto. I don't want to cool in
| the winter under any circumstances. I can simply open a window.
| Vise versa for the summer.
| sigmaisaletter wrote:
| Oh, and if the internet goes down, the programmed schedule should
| still work. Pretty please?
| bhaney wrote:
| If you have any familiarity with basic electronics at all, I
| strongly recommend building your own thermostat. It's very easy
| to connect a few relays and a temperature sensor to an off-the-
| shelf microcontroller. Give it any interface you want. Mine is an
| ESP-32 with a simple API that I control from a little web app or
| some basic push buttons on the thermostat itself in case the
| network is down.
| bityard wrote:
| Do you by any chance have your documented anywhere? I want to
| build my own. (Eventually. One of these days. When I get some
| spare time, of course. Perhaps in retirement...)
| matthewdgreen wrote:
| Since we're dreaming about appliances: could someone please
| design a simple computer-controlled valve that shuts off the
| water and drains the pipes when the house temperature drops below
| a certain point? We very nearly had a $100,000+ home repair when
| a burst pipe shorted out our furnace this winter. This cannot be
| a very hard device to build?
| jyoung8607 wrote:
| The controllable shutoff valves are already a thing, on the
| market. They even measure flow rates and look for slow leaks
| and notify you in an app.
|
| Draining the pipes isn't that simple, and even if you did, you
| still have things like a water heater, toilets, softeners,
| filters, and expansion tanks. You also wouldn't get the water
| sitting in drain traps; winterizing a house or RV involves
| pouring a little RV antifreeze down each drain.
| quickthrowman wrote:
| It's easy to control a valve actuator based on a space
| temperature sensor reading, monitor the space temp and when it
| hits _setpoint_ , send a signal to the valve actuator to open
| up. Add in a flowmeter on your drain pipe and you can even
| close the valve when the water is done draining. Probably there
| is a fitting with a valve and flowmeter in one.
|
| The difficult part is opening up all of the plumbing fixtures
| and taps automatically, I haven't tried draining water out of a
| home's plumbing system without opening all of the taps and am
| unsure if it works.
|
| If you have a well, you'll need to drain the expansion tank and
| turn off the water pump, the latter can be achieved with a
| relay that breaks power to the pump but I'm unsure of how to
| handle the former.
|
| You'll also need to automate filling the traps with antifreeze,
| unless you're cool with replacing sink traps and toilets after
| a freeze event.
| teekert wrote:
| I live in the Netherlands, all our central furnaces speak
| OpenTherm, and still the best option is a Nest v3, it's
| depressing (the device is beautiful but it should just have a
| local API).
|
| Perhaps next time I'll make something like that, using home
| assistant you can easily turn any switch with any temp sensor
| into a thermostat.
| LastTrain wrote:
| Hey if you love to write requirements like "make it a bit warmer
| for two hours" you should come work at my place.
| kimixa wrote:
| I think this is already the "standard" interface for physical
| thermostats in the UK - the house where I was growing up in the
| UK, 4 timers (that can be selected based on "day of week"), a "1
| hour boost" button, and a whole system "on/off".
|
| This was at latest mid-90s, so not exactly "high tech". I don't
| think it's uncommon, as both random rented student house and the
| first place I rented while working had pretty much the same thing
| (though I think the student house only had 2 timers and no "day"
| functionality?). They didn't have air conditioning though, as
| that's not common residentially. And unless the allowed variance
| is also _really_ wide (probably too wide for comfort in some
| situations), I don 't really want the "same" temperature to be
| used for heat and cooling.
|
| I'm surprised how many people I know IRL in the states that think
| this sort of thing is some fundamental tech limitation - like you
| need the latest fancy "smart" thermostat when 99% of what you
| will actually use it for is just "not the cheapest-possible" dumb
| one.
| 0_____0 wrote:
| Engineering: Part count is too high, redo this with max one
| screen and three buttons. You know 7 screens costs almost 7 times
| as much as one screen right?
|
| Industrial Design: [Drops a brick with a photo of Dieter Rams'
| original Braun radio taped to it onto your head from 3 storeys
| up]
|
| Edit: non-joke feedback- this is great from a techie perspective
| but it's too much actual hardware complexity and visual presence
| for a task that will be done maybe twice per season. You have
| added about 50% to the cost of goods sold to do this - is it
| worth it? Will people buy it? Yes I understand this isn't a
| totally serious device proposal, but I would love people to try
| to understand why things end up looking like they do!
| degamad wrote:
| Who says those buttons have to be physical? With the near-
| ubiquity of touchscreen interfaces, that should be trivial to
| build for dirt cheap.
| bhaney wrote:
| Where are you getting touchscreens large enough to
| comfortably fit that entire interface for dirt cheap?
| MostlyStable wrote:
| What I want is a thermostat has basic controls on the device such
| that it can do the basics (heat, cool, circulate air, hold
| temperature at setpoint), but also passes on all the wire states
| over either wifi, zigbee, or one of the other home automation
| standards so that I can make arbitrarily complex control boards
| and routines through homeassistant.
|
| This probably exists for the really basic 4 wire versions, but I
| have a more complicated 8-wire Lennox thermostat and I haven't
| been able to find something like this.
| Ecco wrote:
| Agreed. I really like the hardware (and price point) of
| Amazon's smart thermostat. Unfortunately it's all proprietary
| and locked to Alexa. I really hope someone unlocks them at some
| point.
| floating-io wrote:
| This right here is why I bought the slightly lower-end two-
| speed system instead of the variable-speed system (it's a
| Trane, I believe). I'm just _not interested_ in getting tied
| into their proprietary ecosystem.
|
| I have a relatively simple Honeywell Z-Wave thermostat, and it
| works great with Home Assistant.
| biotinker wrote:
| You want home assistant, as other comments have noted.
|
| I have a reasonably complex set of behavior set up. I live in
| Bend, Oregon at 4000 feet. This is somewhere with hot sunny days,
| cold nights, and sometimes a lot of smoke. The effect on the
| interior of the house based on upcoming weather is highly
| predictable.
|
| My rules look something like this:
|
| If tomorrow's high temperature is above 85, then as today as soon
| as outdoor temperature drops below indoor temperature, open all
| the windows and turn on the attic fan until either interior temp
| is below 62 or outdoor temp rises above indoor, whichever comes
| first. Unless the AQI outside goes over 100 for more than 2
| minutes, in which case close all the windows and turn on the
| fan/AC to clean the air. All the while, if the house rises above
| temperature X, cool it to temperature Y.
|
| Additionally, the upstairs heatpump is located in an uninsulated
| attic, which in winter means that heating is somewhat inefficient
| and we want to run it a minimal count of times to avoid warmup
| periods. So we program in our own hysteresis, so that there's a
| 6-degree difference between when the heat kicks on, and when it
| turns off.
| cstrahan wrote:
| I just want a thermostat that gives me the option to specify that
| I want it to maintain a target temperature, and have it
| automatically switch between cooling and heating.
|
| The one I have in the apartment I'm renting only gives Cool vs
| Heat. With Texas being as finicky as it is this time of year, the
| temperature swings from frigidly cold to swelteringly hot day to
| day, and with my ADHD and lack of connection to my body, I find
| myself wondering why I'm feeling run down and mentally foggy, and
| then I realize it's because I had to switch to Heat yesterday
| (because the house dropped down to 60F) and today the apartment
| is now at 85F, and I've been progressively overheating for the
| past 5 hours or so.
| quickthrowman wrote:
| The key to making a functional automatic switch between heating
| and cooling is an outdoor air temp sensor. You could whip up
| something with a controller, a few relays, and two temp
| sensors, one for inside and one for outside.
|
| A thermostat is dead simple, 24VAC and 4 wires: heat, cool,
| fan, power. You'd need to experiment and figure out where the
| point will be best to switch from heating to cooling based on
| the outdoor air temp, the controller would control this.
|
| There might be commercial products available that do this
| already, but if they don't have an outdoor air temp sensor, it
| won't work.
|
| FWIW I bid and run commercial building automation
| installations.
| bironran wrote:
| Piggybacking on this, I just want an alarm that I could tell "not
| tomorrow please, I'm off work. But keep the schedule otherwise,
| ok?"
|
| Apparently that's touch to ask in 2025.
| __jonas wrote:
| The iPhone does that, when you have a sleep schedule set it
| will show you the alarm for the coming day and when you go turn
| it off it turns it off for the next day only (it prompts you to
| confirm you want to just skip the next one rather than edit the
| schedule). They've got that one figured out, works really well
| for me.
| bhaney wrote:
| The default alarm system of iOS allows for this
| gregschlom wrote:
| Pixel phones have that (pause for a number of days) - not sure
| about other Android or iOS
| brianpan wrote:
| If you happen to be an iOS user you can setup a bedtime. Then
| there are controls to change your sleep/wake times for "next
| wake up only". Or to skip for a day.
| ipunchghosts wrote:
| My Honeywell does everything minus the left pane. Am I missing
| something?
| herpdyderp wrote:
| My house came with a Nest installed and I think it looks cool so
| I left it in but never gave it the wifi password and turned off
| absolutely all the crazy "smart" features it had. Now it's a
| really neat looking dumb thermostat and I want nothing else.
| 418tpot wrote:
| My house also came with a nest, and I also never connected it
| to my network, but for me nest was a terrible dumb thermostat.
|
| It constantly tried to infer schedules and change the
| temperature on its own. I would set the temperature, come back
| an hour later to find that it changed itself back to what it
| thought it should be.
|
| Also, there was no way to just activate the fan. I live in a
| very temperate climate and I generally like to keep a few
| windows open but run the fan to circulate air through the
| house.
|
| I sold the nest and now a $15 dumb thermostat from the local
| hardware store now lets me set a temperature and it won't
| randomly change it when it feels like it. And it has a switch
| to turn on the fan.
| Ecco wrote:
| Personally my dream thermostat would be Amazon's smart
| thermostat, but with a firmware that allows for local control by
| home assistant.
|
| Here's why I think the hardware is so great:
|
| - Simple, high-contrast temperature display (7-segment led)
|
| - Just a few buttons to override temp/mode manually
|
| - Reliable sensor (it's made by Honeywell)
|
| - Nice industrial design (doesn't get in the way)
|
| - Low price point (got it for $49)
|
| I really wish someone would find a way to unlock their firmware.
| I tried to mess with it and figured it did MQTT (yay!) but it
| does certificate pinning :-/ I even opened one up but couldn't
| find an easy way to dump the firmware off of its i.MX chip.
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