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Attacking My Landlord's Boiler

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Re: Attacking My Landlord's Boiler

#71

Post by evrimoztamur »

rightbyte wrote: post #70
sz4kerto wrote: post #58

We've moved to an new apartment (house) and we had to do a full renovation. It doesn't have modern insulation and I calculated that for the time being the ROI on insulation isn't worth it. It's a multi-floor semi-detached house and I wanted the best comfort and the most economical heating possible. In particular: stable and individually adjustable temperatures for bedrooms and living rooms; underfloor heating in some…

Sounds like a nightmare for a future buyer to operate. Some people are unlucky enough to buy homes where a machine engineer designed the boiler setup and the boiler room have enough valves and manometers to like operate the engine of Titanic. I guess programmers are the new sinners in this area nowadays.

The existing professional setup was also a nightmare, what gives?

Re: Attacking My Landlord's Boiler

#72

Post by frontlodjkgi »

rsynnott wrote: post #62

Some risk of collateral damage in the form of randomly controlling other peoples' boilers if your transmitter turns out to be more powerful than the one in the thermostat, tho...

I imagine even encrypted messages could be replayed if the protocol wasn't designed against it. It also doesen't say what kind of encryption it uses, it could be a very weak in-house "encryption", for all we know it could be only an unknown encoding.

Re: Attacking My Landlord's Boiler

#73

Post by DamonHD »

tgsovlerkhgsel wrote: post #46
Cthulhu_ wrote: post #38

Earlier quoted context omitted.

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…

> 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.

This is a whole research topic, my PhD in fact!

FWIW I run my heat pump intermittently and with locally-smart TRVs that get to call for heat centrally, and a weather compensation only flow temperature curve, and it WORKSFORME!

https://www.earth.org.uk/heat-pump-16WW-control.html

Re: Attacking My Landlord's Boiler

#74

Post by leoedin »

frereubu wrote: post #54
sokoloff wrote: post #50

> 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…

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.

Re: Attacking My Landlord's Boiler

#75

Post by DamonHD »

Retric wrote: post #59
sokoloff wrote: post #50

> 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…

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 become…

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.

Re: Attacking My Landlord's Boiler

#77

Post by 0xEF »

DecoPerson wrote: post #56

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…

> 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.

Re: Attacking My Landlord's Boiler

#78

Post by rightbyte »

evrimoztamur wrote: post #71
rightbyte wrote: post #70

Earlier quoted context omitted.

Sounds like a nightmare for a future buyer to operate. Some people are unlucky enough to buy homes where a machine engineer designed the boiler setup and the boiler room have enough valves and manometers to like operate the engine of Titanic. I guess programmers are the new sinners in this area nowadays.

The existing professional setup was also a nightmare, what gives?

Well first of I am envious and I would want to do something similar.

If I inherit a heating system I want it to be all mechanical except maybe the control system for any heating pump.

Re: Attacking My Landlord's Boiler

#79

Post by rightbyte »

tgsovlerkhgsel wrote: post #46
Cthulhu_ wrote: post #38

Earlier quoted context omitted.

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…

> 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.

"Quickly" implies higher power which will make the air around radiators warmer than a slow heating.

The losses are proportional to the temperature differential between outside and inside.

So you should have somewhat higher losses from the hotter air streams from the radiators passing the windows.

Dunno about magnitude though.

Re: Attacking My Landlord's Boiler

#80

Post by gRoberts84 »

I went through various stages of this myself and got an Sonoff RF Bridge, that allowed me to capture and replay RF via Home Assistant. In the end though, it was always easier to use an off the shelf solution, especially for boilers. OpenTherm with Tado worked perfectly.
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