Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Attacking My Landlord's Boiler

blog.videah.net

Post reply on HN
Print view View original

61–70 of 232 posts

Re: Attacking My Landlord's Boiler

#61

Post by sz4kerto »

wickedsight wrote: post #45
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 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 g…

It does match physics if you consider other factors. Apart from the heat pump scenario, this statement can also be true when you have condensing boilers (and okay-ish insulation)

The reasoning: when you heat up the house, then your boiler needs to produce constant high-temperature water. When you keep the house at the same temperature, then the boiler produces much lower temp water and it is more efficient.

Insulation also matters because if your house has outer insulation then it means that heat transfer from the house to the environment is mostly blocked, but cross-room heat transfer is likely not (through the walls). Therefore it is better to heat the whole house than heating just a couple of rooms because if you do the latter then you'll end up heating the whole house anyway but you're using less surface area (meaning you need higher flow temperatures, meaning less efficiency).

Re: Attacking My Landlord's Boiler

#63

Post by sz4kerto »

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…

> 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.

Re: Attacking My Landlord's Boiler

#64

Post by Retric »

sokoloff wrote: post #60
frereubu wrote: post #54

Earlier quoted context omitted.

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?

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 tr…

> 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.

You’ve got the first part of that backwards, it’s the walls near your radiators that are your problem and need more insulation.

Re: Attacking My Landlord's Boiler

#65

Post by darkwater »

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…

Yeah, the automated/remote controlled heating system world, and also the ringbell world is basically a giant scam, since they are updates on world that also scammed you in the past. I cried when I shelled out so much money for my Tado device, but even a dumb bTicino device costed in the hundred of euros realm, and it's just a sensor + a small LCD display and a designed-in-hell menu system to program it. And the same happens in Ip-based ringbells. A Doorbird will cost you hundreds of euros for what is basically a webcam plus some nice metal casing and a shitty software, but it competes with analog systems with optic cables etc that cost basically the same or more.

Re: Attacking My Landlord's Boiler

#66

Post by sokoloff »

sz4kerto wrote: post #63
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…

> 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.

Indeed “depends” is almost always the answer.

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.

Re: Attacking My Landlord's Boiler

#67

Post by robocat »

> sledgehammer approach

A hammerier solution would be to control the temperature seen by the thermostat (ignore the difficult RF protocol).

A heating element and a temperature reading could control the heat seen by the thermostat.

I'm pretty sure you wouldn't need any cooling (Peltier or whatever). Just a heater and ambient cooling! Set the thermostat to a high temperature, and run the heater to make the measured temperature hotter: when you don't want the heating to run.

That said, I think hacking the RF protocol is geekier and far awesomer.

Re: Attacking My Landlord's Boiler

#68

Post by Tarq0n »

odiroot wrote: post #21
glitchcrab wrote: post #14

Earlier quoted context omitted.

I think you missed where it was explained that the apartment is rented and therefore you cannot modify anything.

Replacing a thermostat is very easy to do though. And very easy to revert too. 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.

OP's thermostat wasn't wired, that's why he'd need the electrician.

Re: Attacking My Landlord's Boiler

#69

Post by sokoloff »

Retric wrote: post #64
sokoloff wrote: post #60

Earlier quoted context omitted.

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 tr…

> 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. You’ve got the first part of that backwards, it’s the walls near your radiators that are your problem and need more insulation.

Indeed the building is 100 years old and impractical to retrofit insulation in any cost-efficient way (structural brick, lathe and plaster walls with about 1” of air space in the original parts of the building).

Re: Attacking My Landlord's Boiler

#70

Post by rightbyte »

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.

Post reply on HN