> I also have it so the heating turns off when I go into town and turns back on when I'm just a few train stops away so my place is nice and toasty for me getting home!
If your goal is saving energy/money, you don’t want a system capable of going from cool to toasty in 20 minutes.
Instead, you want a system that runs (much) lower water circulation temperatures (giving lower losses in the unconditioned spaces and more even room heating). That can be done to any condensing boiler by just turning down the flow target temperature.
A second layer of optimization on top of this is the addition of outdoor reset/weather compensation which will adjust that flow temperature based on the outside temperature, giving a flow temperature than can just barely restore the building to the desired setpoint temp.
With mine properly tuned, I was targeting having the thermostat act more like a high-limit and for it to call for heat between 22 and 24 hours per day while not overheating the house. That often meant flow temps in the 110°F (warm day) to 135°F (below freezing day) range. Compared to the prior winter (at a constant 160°F flow), the house used 8-15% less gas and was wildly more comfortable. (This setup does preclude using deep setback settings, which also can save money, because recovery times are necessarily long in such a scheme, unless you have an even smarter control system that can run perfectly tuned water most times but hotter water during recovery from setbacks.)
That’s an artifact of how heating is setup inside your home. Which is more efficient depends on where you’re dumping heat inside the home, levels of insulation, etc.
Energy moves from hot to cold linearly with temperature differences. Hypothetically, if the pipe was the same temperatures as the inside of your home all the heat transferred would be outside the envelope. The hotter the pipe the better this ratio becomes. This is true regardless of what percentage of the pipe is inside the envelope.
However, heating along the exterior of the home under windows and such then you’ll heat the exterior walls to higher temperatures than the interior thermostat thus losing more heat to the outside. Radiant heating on the other hand largely avoids this effect.
Look at ISO 7730, a lot of comfort comes from non-cold walls and their radiant heat and small difference of wall temperatures to air temperatures. So having a thoroughly heated home allows you to lower your air temperature. Apart from that modern gas and even more heat pumps greatly gain efficiency by lowering flow water temperatures.
I moved all my radiators away from under windows (and upgraded the windows to triple glazing) to avoid maximising the temperature differential and energy loss through the wall under the windows, while eliminating the cool drafts that the under-window radiator placement was intended to counter.
Agree, switching on and off is the worst way of heating. If you look into ISO 7730, then a lot of comfort comes from non cold walls: https://de.wikipedia.org/wiki/ISO_7730
This means that in a reasonable insulated home, your best bet for comfort is to just keep the temperature constant and low like 20°C. This also allows you to lower your water temperatures which improves efficiency of your heat pump or boiler.
Depending on the region, "reasonably insulated home" really is the factor that makes this not so viable for a lot of people. In my Mediterranean-adjacent climate country, most homes are just not well insulated at all, and having heat running 24/7 during winter is extremely costly and inefficient even if the heating is on a low setting.
I used to divide my time between a concrete hulk of a NYC apartment building, and a California home insulated to notoriously poor California standards. I was plenty warm in New York winters just from my neighbors' heat nearly all of the time. In California, there was a narrow window (think "Apollo 13 re-entry") between too cold and too warm.
Then we modernized ceiling fans, and I hit on running them in "winter mode" drawing hot air up to flow back down the walls. Bingo! I love that ISO 7730 confirms this.
I've read that it's always more efficient to turn heating off when you're not home and then turn it back on when you return. Is the reason for it being on 22-24 hours here that it takes a very long time to get back to the desired temperature, meaning you'd actually be cold for quite a while as it returned to the desired temperature?
The hidden factor here is that condensing boilers and heat pumps have non-linear efficiency vs flow temperature curves. Heat pumps in particular show high increase in coefficient of performance (CoP) as flow temperature drops.
The other variable is how well controlled your heating is. A lower flow temperature means less overshoot of the target set point - and as losses scale linearly with temperature delta, that can mean higher energy losses (depending on the characteristics of the controller of course).
Whether or not you care about losses in unheated spaces depends on your system topology. Personally, all my heating pipes are within the thermal envelope of my house, so flow temperature has no bearing on those losses at all.
If you had a resistive electric boiler, flow temperature would have absolutely no effect on efficiency. You'd be completely right, that running heating only when you needed it would be more energy efficient.
> I've read that it's always more efficient to turn heating off when you're not home and then turn it back on when you return.
50 years ago this was _always_ the case, but condensing boilers and especially heat pumps muddy the waters a little. Condensing boilers can be close to 100% efficient (vs ~70-80% for ye olde gas boilers), but generally only at a fairly specific operating temperature, which may be lower than you'd need to get a rapid rise in temperature. Heatpumps are >100% efficient (that is for every joule of electricity you put in they move more than one joule), but are even more fussy about operating temperature.
The answer now is going to be a solid 'it depends', based on behaviour of the heating system, outside temp, desired inside temp, insulation...
I work entirely remote so, other than travel, there are not many long periods when the house is unoccupied.
I target the long run time to maximize efficiency. A 160°F pipe will lose more heat to the part of the building that I don’t want to heat as well as more heat to the wall right behind the radiators. It also results in the house going micro too-hot, too-cold, too-hot, too-cold as it cycles. Mine is constantly trickling in just enough heat to replace the heat lost instead of cycling between adding way more than needed then none for a while.
Another large effect is that low return water temperatures into the boiler allow for greater condensation of exhaust gas energy to be used in the building instead of sent outside. Walking by my house on a cold day, you’ll see minimal steam plume during operation. All that steam I see my neighbors emitting is energy they paid for and delivered to the outside… (They paid a lot for a boiler with a 95% or 98% sticker and run it at 80% efficiency.)
Unsure if what you posted is true because I don’t know about water based systems, however this has been proven false for heat pumps.
Specifically, setting a fixed temp vs turning things up/down/off when you are leaving and reversing it before you get home. There was little difference either way. The amount of electricity consumed was similar to both.
I wish I had a link, they even tested cases where efficiency was lost heating things up. This includes “emergency heating”.
> If your goal is saving energy/money, you don’t want a system capable of going from cool to toasty in 20 minutes.
Depends. As explained in a sibling comments, I have some rooms that have combined UFH and radiators, and if the desired temp is more than 1 celsius away from the current temp, then both are driven, otherwise it's just the UFH.
So long as you can get the boiler return water temps low enough, you can operate the boiler in its high efficiency range.
Most dual-temp setups are set for the highest temp and mixed-down to provide the lower temp for under-floor. That’s cheapest in terms of equipment and install but cannot be as efficient as a system that mixes down when both loads call but also lowers flow temp (thereby lowering return temp) when no high-temp rads are calling.
This is a great post which describes how most commercial boilers are controlled. I’m looking at a sequence of operations for a boiler project I did recently and the hot water supply setpoint for -20F outdoor air is 145F and for +45F the hot water supply setpoint is 120F.
Most home boilers lack an outdoor air reference temp sensor but all commercial boilers have them.
Also, condensing boilers are amazing, the size difference alone vs an old tube boiler is wild, very small in comparison.
Capable doesn't mean it always puts out that amount of heat.
A well-designed system would have good insulation, can dump 10000W watts of heat out and bring the room from cool to toasty in 5 minutes, and then scale back and maintain the temperature after that by putting out 500W after that.
This also tends to be more efficient in practice because if you know it only takes 5 minutes to heat up you are less likely to want to leave it on when you're not around.
But it can't heat up the walls and other surfaces in that amount of time. The building will feel colder for the same air temperature setting until those objects have had time to warm up as well.
It seems like the easier hack would be to put a peltier heater/cooler under the thermostat then control that remotely to assume control over what temperature the thermostat sees.
The link to the exact model of thermostat isn't working, so I don't know how amenable its design is to this approach, but the thermostats I've used are generally wall-mounted and putting a heat/cool source under them wouldn't be too hard. You'd need to make sure that you didn't send both the heat and cool into the thermostat, but that's a simple positioning problem.
Actually the best control system for such a boiler would be to control the heating curve where heating water temperature is fixed to the outside temperature. If you aim for the lowest water temperatures possible, then the system will become quite slow reacting. Then you only need to adjust the flow of water to the individual rooms to fix varying temperature issue. But this is long term manual optimization process which takes 1 to 2 years to perfect.
I guess your toolbox really shapes your solution space thinking; as I read through this, being completely lost in the whole world of RF whatnot, my mind jumped straight to an alternative attack that better fit my own tooling: could you encase the thermostat in a box that you can mechanically control the temperature of?
I removed the thermistor from inside my wall controller and wired in a digital pot instead. Achieves the same thing without physically heating and cooling the sensor
The problem is, if your landlord ever comes around for inspection, or the bloody thing breaks down due to your installation attempt, you can be held liable up to and including getting evicted.
This sounds good, except that cooling a box is problematic. He needs the temperature sensor to read low so that it turns on the heat.
That said, if he has access to the interior of the thermostat, I'm sure it won't be difficult to replace the temperature sensor with a circuit to cause it to read either really high or really low on demand.
I was literally imagining duck-taping one of those cheap electric "instant cooling" cups over the box on the wall, and running a small incandescent bulb in to be the heating up element.
Or, assuming they have physical access to the combi boiler, removing the receiver unit and replacing it with a more Home Assistant friendly combi boiler thermostat.
Probably a 30 minute job if you’ve never done it before and easily reversible with a little bit of double sided sticky tape, which all Brits should be familiar with if they ever made a Tracy Island. There is a real risk of electrocution which could be completely militated against by turning off the power to the boiler.
I heard that was a well-known trick at my old uni dorm. There was a single thermostat for the whole floor so once people figured out where the sensor was, the ones who lived closest to it would often leave packs of frozen food on it.
I wonder what the ideal one-size fits all thermostat looks like.
The one in my apartment has a “feature” a lot of US thermostats now have, where you set four ordered times called wake, leave, return, and sleep and the temperature you want the space in each interval. I know very few people who actually live in a household where everyone wakes, leaves, returns, and sleeps on the same schedule every day.
I work from home and personally just want to set a temperature and have the space stay at that temperature indefinitely but this system requires that I tap through and enter the desired temperature four times, while confirming the four intervals.
I guess I’d be happier with a more programmable thermostat that I could set to behave like an old school dial thermostat.
I'm still of the opinion that a dial works best. Especially in modern homes (in Europe at least), there seems to be a school of thought that you should just leave your thermostat at the same temperature at all times - the theory being that warming up a cold house in the morning costs more energy than maintaining a stable temperature.
Anyway, my ideal setup would be to install 'smart' thermostat taps on every radiator in the house, either manually turn them down when you're not in the room or have them automatically detect activity or open windows and adjust accordingly. But each one has the authority to trigger the central boiler if needs be, instead of only the master thermostat in the living room.
> the theory being that warming up a cold house in the morning costs more energy than maintaining a stable temperature
This is only true if the heating happens quickly and the system is less efficient when heating quickly. Otherwise, this doesn't make sense from a physics standpoint. A temporarily lower temperature differential means less kWh of heat lost.
> the theory being that warming up a cold house in the morning costs more energy than maintaining a stable temperature
I've heard this theory a lot too, but it doesn't match with physics. A warm house loses more energy than a cold house, due to a higher temperature difference allowing easier heat transfer. So in most homes, with radiators and high temperature CV, it's way more efficient to just turn it off when you gone.
One exception is when you have a very well insulated house, combined with floor heating and a very efficient, low temperature heat pump. In this case, it takes a lot of time for temperature to move in the house and it's already incredibly efficient.
I think in real life there are more constraints. For example there are people that sleep better at a lower temperature than the daily one (so leaving the thermostat at the same temperature it's a minus for them).
Regarding "what is better" from energy efficiency, I would prefer a system that "check it" because my guess is that it depends a lot based on the individual situation. I mean everybody is going crazy over "IA" but a couple of sensors and a system smart enough to adjust your usage based on your particular situation and preferences (like "eco", etc.) is an exception.
(UK) my boiler has a control with something like the wake..leave timer (it actually has six settings for a midday period as well) and there is a separate thermostat with a temperature dial. The boiler also has a button that advances it to the next time interval if you want instant on (eg if you come home early to a cold house). I find this combo of controls meets all of my needs, given that I have a fairly repeatable daily schedule.
We've used the Tado system with a central boiler and smart radiator knobs for a few years. It's worked fine and hooks up to Home Assistant and can do the things you describe. I'm sure there are some alternatives.
I have an Ecobee and I like it. It comes standard with Home, Away, and Sleep but you can put in as many or as few as you want. You can manually change the temp and you can also set how long you want your manual temp to “stick”. Either until you cancel it, or until the next preprogrammed change. I like it cooler at night, so I have it change temp around my normal bedtime, which includes if I adjusted the daytime temp because I don’t want to have to remember to change it back myself, that’s why I have a smart thermostat. It detects when I leave the house and sets it to away, because I don’t need it running as if I am at home. If I go on vacation I can set it to keep the house safe, but not comfortable, and change back around the time my flight lands.
Unless you have a crazy random schedule, or you want the temp the same whether you are asleep, awake, or not at home, or i guess if you have different temp preferences every day. Otherwise you can program in a basic schedule and just adjust manually as needed. Nothing stops you from changing the temp manually if you wake up an hour early, but if you wake up on time, then you don’t even have to think about it.
>I guess I’d be happier with a more programmable thermostat that I could set to behave like an old school dial thermostat.
I honestly prefer the older type. Ours is programable, but we just don't program it and always just set it to the temp we want. If we are feeling a little chilly on a cold day, we'll bump it up a degree, or down a degree when it's particularly sunny and everyone is feeling warm.
Isn't this pretty much what these thermostats already allow? I have a new Honeywell Thermostat which basically does what the twenty years old one it replaced does with a few added conveniences in terms of UI. It has those wake/leave/return/sleep instants for each weekday (but also adds an optional second leave/return pair), and it has an option to override the day programme to 'holiday', which is essentially an eighth programmable weekday you can activate at any time.
Your use case is possible with that. Just set the standard program to 15°C, and activate the holiday set to whatever you need whenever you want. Configure it to go to 15°C at some sensible time in the evening, so it won't go on even if you forget it.
The obvious solution is a "wake time" of 8 am, "leave time" of 8:01, "return" 8:02, "sleep" 8:03. Then just set the sleep temperature to your desired temp and the remaining ones to something reasonably close, or if it doesn't automatically switch between heating and air conditioning, set it for the no-op for the season (i.e. the highest possible temp in summer, and the lowest possible in winter) for those three minutes.
My wife and I worked a six-week shift work schedule for a long time. We got second-gen nest thermostats when they first came out (2012) thinking they were neat.
Nope! The smart learning feature was the biggest pain in the ass. You’d be sleeping during the day for a night shift, only to find yourself freezing because it decided no one was home.
Mine works OK as long as presence detection (using people's phones and Google Home) is operating correctly.
Everyone leaves, and the thermostat adjusts.
Someone comes home (or walks in front of it), and it goes back to the normal setpoint.
Sounds easy. Isn't always easy.
The reliability of this seems to be highly dependent on the phone(s) themselves simply succeeding at not killing useful processes.
Overall, I'm not entirely displeased with it. I procured it very inexpensively by buying it from one of my energy provider's online store in conjunction with a substantial rebate from my other energy provider. I'm confident that it paid for itself very quickly, and it's nice to be able to set the thermostat remotely.
My lament is that there seems to be approximately nothing I can do to improve the presence detection function without gymnastics or spending real money. What I want is a local API that I can enable and do stuff with; what I get is "Good luck! Have you tried buying Nest Protect subscription motion detectors? (Oh lol, we stopped selling those.)"
(I'm OK with the privacy and security aspects of what I'm trying to do. I'm not OK with having a connected device that I can't bend to my will. I'm even less OK with more recurring expenses. The next thermostat I buy will have local control over the LAN, but it probably won't pay for itself quite as quickly as this one did.)
[note: I've never played with the auto-schedule "learning" function at all. It always seemed like a complete waste of time, since I for one do not have a regular schedule.]
The Flipper Zero is great, and could handle all of the hacking/investigation part by installing custom firmware.
The original product understandably arrives with heavily-restricted firmware (I imagine to reduce the amount of flak the company receives). However, it is incredibly easy to install Flipper Unleashed or similar, which removes all said restrictions and adds a lot of additional functionality.
Possessing the tools that could be used to commit a crime is not necessarily a crime in and of itself! Just be careful with what you do or, depending on what country you’re in, you might find some men in suits knocking at your door.
Personally, I wanted to replay “encrypted” 433MHz signals for my own devices (electric gate, roller door, roller shutters, …) and this was disabled with the Flipper’s region set to Australia.
> Possessing the tools that could be used to commit a crime is not necessarily a crime in and of itself!
While I do agree 1000%, I also want people to be careful with this thinking since I have gotten in some minor trouble in the past. Always assume the authority questioning you can and will create whatever narrative they wish, that it will be accepted, and that your own reasoning will likely be used against you.
I will always encourage exploration and curiosity in tech, but if we stick with the Flipper Zero example, there's a few things one should keep in mind, regardless of the jurisdiction they're in:
* Don't carry it around unless you intend to use it.
* Read all documentation before you start practicing, then practice being subtle.
* Taking a note from my outdoorsy side, adopt the "leave no trace" ethos.
* Pay attention to the effect your presence and actions have on the environment and your target and how that might be interpreted by an outside observer, then take action to mitigate suspicion.
These apply to lots of devices, everything from your disposable smartphone to a cheap RFID card copier from Temu.
Our eagerness sometimes gets the best of us, especially new-comers, and we want to jump to the part where we can be like the hackers we see in tv and video games. There's a reason those guys are fictional characters. Innocuous actions or not, the perception of the authority questioning you is all that will matter, in the end.
> "Always assume the authority questioning you can and will create whatever narrative they wish, that it will be accepted, and that your own reasoning will likely be used against you."
I would probably just go about this by heating/cooling the thermostat itself rather than messing around with radio signals. Put a little box around it and something that could control the temp in the box, like a little peltier element. When you want the heat to run, cool the inside of the box. When you want it to stop, warm it up. Etc.
But then I build thermal control devices for fun so maybe it just seems like a much easier method to me.
If OP ever shows up here, you probably could have just replaced the thermostat with one that is compatible with your boiler for less money and headache. The boiler market is fairly open to competition as evidenced by the fact that you could find a Honeywell signal in a random OSS project that also worked.
Good luck with your future apartment customizations!
Depends on jurisdiction, of course, but often you’re allowed to modify things as long as you return it to how it was before when you leave. Obviously not quite as simple as that always but I would guess in many placing temporarily replacing a simple thermostat would fall under that.
You just take the thermostat off the wall and put it in a drawer and then you buy a new thermostat and put it on the wall and then when you give the apartment back, you take the old thermostat and you put it back on the wall
Also, if you read this far, are you German or something? you can just do things. which OP seems to know. And even if the landlord came and saw the apartment as long as the new thermostat isn’t neon orange, he isn’t going to notice and even if he somehow noticed you would just gaslight him and say no that’s how it’s always been and how the hell is he gonna escalate past that? And why would he if the new thermostat is more expensive and has better features?
Readit News
If your goal is saving energy/money, you don’t want a system capable of going from cool to toasty in 20 minutes.
Instead, you want a system that runs (much) lower water circulation temperatures (giving lower losses in the unconditioned spaces and more even room heating). That can be done to any condensing boiler by just turning down the flow target temperature.
A second layer of optimization on top of this is the addition of outdoor reset/weather compensation which will adjust that flow temperature based on the outside temperature, giving a flow temperature than can just barely restore the building to the desired setpoint temp.
With mine properly tuned, I was targeting having the thermostat act more like a high-limit and for it to call for heat between 22 and 24 hours per day while not overheating the house. That often meant flow temps in the 110°F (warm day) to 135°F (below freezing day) range. Compared to the prior winter (at a constant 160°F flow), the house used 8-15% less gas and was wildly more comfortable. (This setup does preclude using deep setback settings, which also can save money, because recovery times are necessarily long in such a scheme, unless you have an even smarter control system that can run perfectly tuned water most times but hotter water during recovery from setbacks.)
Energy moves from hot to cold linearly with temperature differences. Hypothetically, if the pipe was the same temperatures as the inside of your home all the heat transferred would be outside the envelope. The hotter the pipe the better this ratio becomes. This is true regardless of what percentage of the pipe is inside the envelope.
However, heating along the exterior of the home under windows and such then you’ll heat the exterior walls to higher temperatures than the interior thermostat thus losing more heat to the outside. Radiant heating on the other hand largely avoids this effect.
I used to divide my time between a concrete hulk of a NYC apartment building, and a California home insulated to notoriously poor California standards. I was plenty warm in New York winters just from my neighbors' heat nearly all of the time. In California, there was a narrow window (think "Apollo 13 re-entry") between too cold and too warm.
Then we modernized ceiling fans, and I hit on running them in "winter mode" drawing hot air up to flow back down the walls. Bingo! I love that ISO 7730 confirms this.
The other variable is how well controlled your heating is. A lower flow temperature means less overshoot of the target set point - and as losses scale linearly with temperature delta, that can mean higher energy losses (depending on the characteristics of the controller of course).
Whether or not you care about losses in unheated spaces depends on your system topology. Personally, all my heating pipes are within the thermal envelope of my house, so flow temperature has no bearing on those losses at all.
If you had a resistive electric boiler, flow temperature would have absolutely no effect on efficiency. You'd be completely right, that running heating only when you needed it would be more energy efficient.
50 years ago this was _always_ the case, but condensing boilers and especially heat pumps muddy the waters a little. Condensing boilers can be close to 100% efficient (vs ~70-80% for ye olde gas boilers), but generally only at a fairly specific operating temperature, which may be lower than you'd need to get a rapid rise in temperature. Heatpumps are >100% efficient (that is for every joule of electricity you put in they move more than one joule), but are even more fussy about operating temperature.
The answer now is going to be a solid 'it depends', based on behaviour of the heating system, outside temp, desired inside temp, insulation...
I target the long run time to maximize efficiency. A 160°F pipe will lose more heat to the part of the building that I don’t want to heat as well as more heat to the wall right behind the radiators. It also results in the house going micro too-hot, too-cold, too-hot, too-cold as it cycles. Mine is constantly trickling in just enough heat to replace the heat lost instead of cycling between adding way more than needed then none for a while.
Another large effect is that low return water temperatures into the boiler allow for greater condensation of exhaust gas energy to be used in the building instead of sent outside. Walking by my house on a cold day, you’ll see minimal steam plume during operation. All that steam I see my neighbors emitting is energy they paid for and delivered to the outside… (They paid a lot for a boiler with a 95% or 98% sticker and run it at 80% efficiency.)
https://kw-engineering.com/how-to-optimize-condensing-boiler...
Specifically, setting a fixed temp vs turning things up/down/off when you are leaving and reversing it before you get home. There was little difference either way. The amount of electricity consumed was similar to both.
I wish I had a link, they even tested cases where efficiency was lost heating things up. This includes “emergency heating”.
Depends. As explained in a sibling comments, I have some rooms that have combined UFH and radiators, and if the desired temp is more than 1 celsius away from the current temp, then both are driven, otherwise it's just the UFH.
So long as you can get the boiler return water temps low enough, you can operate the boiler in its high efficiency range.
Most dual-temp setups are set for the highest temp and mixed-down to provide the lower temp for under-floor. That’s cheapest in terms of equipment and install but cannot be as efficient as a system that mixes down when both loads call but also lowers flow temp (thereby lowering return temp) when no high-temp rads are calling.
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Most home boilers lack an outdoor air reference temp sensor but all commercial boilers have them.
Also, condensing boilers are amazing, the size difference alone vs an old tube boiler is wild, very small in comparison.
A well-designed system would have good insulation, can dump 10000W watts of heat out and bring the room from cool to toasty in 5 minutes, and then scale back and maintain the temperature after that by putting out 500W after that.
This also tends to be more efficient in practice because if you know it only takes 5 minutes to heat up you are less likely to want to leave it on when you're not around.
It seems like the easier hack would be to put a peltier heater/cooler under the thermostat then control that remotely to assume control over what temperature the thermostat sees.
The link to the exact model of thermostat isn't working, so I don't know how amenable its design is to this approach, but the thermostats I've used are generally wall-mounted and putting a heat/cool source under them wouldn't be too hard. You'd need to make sure that you didn't send both the heat and cool into the thermostat, but that's a simple positioning problem.
That said, if he has access to the interior of the thermostat, I'm sure it won't be difficult to replace the temperature sensor with a circuit to cause it to read either really high or really low on demand.
Ice pack and desiccant?
Probably a 30 minute job if you’ve never done it before and easily reversible with a little bit of double sided sticky tape, which all Brits should be familiar with if they ever made a Tracy Island. There is a real risk of electrocution which could be completely militated against by turning off the power to the boiler.
Still, a fun hack, and nicely executed!
The one in my apartment has a “feature” a lot of US thermostats now have, where you set four ordered times called wake, leave, return, and sleep and the temperature you want the space in each interval. I know very few people who actually live in a household where everyone wakes, leaves, returns, and sleeps on the same schedule every day.
I work from home and personally just want to set a temperature and have the space stay at that temperature indefinitely but this system requires that I tap through and enter the desired temperature four times, while confirming the four intervals.
I guess I’d be happier with a more programmable thermostat that I could set to behave like an old school dial thermostat.
Anyway, my ideal setup would be to install 'smart' thermostat taps on every radiator in the house, either manually turn them down when you're not in the room or have them automatically detect activity or open windows and adjust accordingly. But each one has the authority to trigger the central boiler if needs be, instead of only the master thermostat in the living room.
This is only true if the heating happens quickly and the system is less efficient when heating quickly. Otherwise, this doesn't make sense from a physics standpoint. A temporarily lower temperature differential means less kWh of heat lost.
I've heard this theory a lot too, but it doesn't match with physics. A warm house loses more energy than a cold house, due to a higher temperature difference allowing easier heat transfer. So in most homes, with radiators and high temperature CV, it's way more efficient to just turn it off when you gone.
One exception is when you have a very well insulated house, combined with floor heating and a very efficient, low temperature heat pump. In this case, it takes a lot of time for temperature to move in the house and it's already incredibly efficient.
Regarding "what is better" from energy efficiency, I would prefer a system that "check it" because my guess is that it depends a lot based on the individual situation. I mean everybody is going crazy over "IA" but a couple of sensors and a system smart enough to adjust your usage based on your particular situation and preferences (like "eco", etc.) is an exception.
That's true if you completely stop heating. However if you lower the temperature by roughly 3.5C when you're not home, you'll be saving energy.
So you can for example program it to be 16C when you're out and 19C when you're in. You don't completely turn off heating indeed.
Unless you have a crazy random schedule, or you want the temp the same whether you are asleep, awake, or not at home, or i guess if you have different temp preferences every day. Otherwise you can program in a basic schedule and just adjust manually as needed. Nothing stops you from changing the temp manually if you wake up an hour early, but if you wake up on time, then you don’t even have to think about it.
I honestly prefer the older type. Ours is programable, but we just don't program it and always just set it to the temp we want. If we are feeling a little chilly on a cold day, we'll bump it up a degree, or down a degree when it's particularly sunny and everyone is feeling warm.
Your use case is possible with that. Just set the standard program to 15°C, and activate the holiday set to whatever you need whenever you want. Configure it to go to 15°C at some sensible time in the evening, so it won't go on even if you forget it.
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The round Honeywell electromechanical thermostat with a bimetallic strip, invented in 1953: https://www.honeywellstore.com/store/products/honeywell-roun...
24VAC, dead simple, and reliable. My family’s lake house has 50+ year old Honeywell round thermostats still in service.
https://www.honeywellhome.com/us/en/products/air/thermostats...
As you go on to describe, there probably isn't one.
Nope! The smart learning feature was the biggest pain in the ass. You’d be sleeping during the day for a night shift, only to find yourself freezing because it decided no one was home.
Everyone leaves, and the thermostat adjusts.
Someone comes home (or walks in front of it), and it goes back to the normal setpoint.
Sounds easy. Isn't always easy.
The reliability of this seems to be highly dependent on the phone(s) themselves simply succeeding at not killing useful processes.
Overall, I'm not entirely displeased with it. I procured it very inexpensively by buying it from one of my energy provider's online store in conjunction with a substantial rebate from my other energy provider. I'm confident that it paid for itself very quickly, and it's nice to be able to set the thermostat remotely.
My lament is that there seems to be approximately nothing I can do to improve the presence detection function without gymnastics or spending real money. What I want is a local API that I can enable and do stuff with; what I get is "Good luck! Have you tried buying Nest Protect subscription motion detectors? (Oh lol, we stopped selling those.)"
(I'm OK with the privacy and security aspects of what I'm trying to do. I'm not OK with having a connected device that I can't bend to my will. I'm even less OK with more recurring expenses. The next thermostat I buy will have local control over the LAN, but it probably won't pay for itself quite as quickly as this one did.)
[note: I've never played with the auto-schedule "learning" function at all. It always seemed like a complete waste of time, since I for one do not have a regular schedule.]
The original product understandably arrives with heavily-restricted firmware (I imagine to reduce the amount of flak the company receives). However, it is incredibly easy to install Flipper Unleashed or similar, which removes all said restrictions and adds a lot of additional functionality.
Possessing the tools that could be used to commit a crime is not necessarily a crime in and of itself! Just be careful with what you do or, depending on what country you’re in, you might find some men in suits knocking at your door.
Personally, I wanted to replay “encrypted” 433MHz signals for my own devices (electric gate, roller door, roller shutters, …) and this was disabled with the Flipper’s region set to Australia.
While I do agree 1000%, I also want people to be careful with this thinking since I have gotten in some minor trouble in the past. Always assume the authority questioning you can and will create whatever narrative they wish, that it will be accepted, and that your own reasoning will likely be used against you.
I will always encourage exploration and curiosity in tech, but if we stick with the Flipper Zero example, there's a few things one should keep in mind, regardless of the jurisdiction they're in:
* Don't carry it around unless you intend to use it.
* Read all documentation before you start practicing, then practice being subtle.
* Taking a note from my outdoorsy side, adopt the "leave no trace" ethos.
* Pay attention to the effect your presence and actions have on the environment and your target and how that might be interpreted by an outside observer, then take action to mitigate suspicion.
These apply to lots of devices, everything from your disposable smartphone to a cheap RFID card copier from Temu.
Our eagerness sometimes gets the best of us, especially new-comers, and we want to jump to the part where we can be like the hackers we see in tv and video games. There's a reason those guys are fictional characters. Innocuous actions or not, the perception of the authority questioning you is all that will matter, in the end.
And with that, I give you:
Don't Talk To the Police:
https://www.youtube.com/watch?v=d-7o9xYp7eE
https://blog.habets.se/2017/04/Decoding-FSK.html
But then I build thermal control devices for fun so maybe it just seems like a much easier method to me.
[0]: https://thex10shop.com/products/x10-powerhouse-th2807-thermo...
Good luck with your future apartment customizations!
Usually it's just acting as a simple relay (on-off switch) so there's two physical wires.
I've got my Hive thermostat running great with various Bosch and Vaillant boilers. And it works great with HA.
Some newer boilers have 12V "smart" controls but still expose 230V "dumb" call for heating pins.
Also, if you read this far, are you German or something? you can just do things. which OP seems to know. And even if the landlord came and saw the apartment as long as the new thermostat isn’t neon orange, he isn’t going to notice and even if he somehow noticed you would just gaslight him and say no that’s how it’s always been and how the hell is he gonna escalate past that? And why would he if the new thermostat is more expensive and has better features?