Controls before Replacement Systems

The home heating industry is in turmoil. Alternative technologies silently vie for control of the wallets of homeowners. As you read this, yet more innocent homeowners are being conditioned to believe that nothing short of spending thousands upon thousands to replace what they already have can save our little blue planet… God help us!

While we all need to act more responsibly, this feels to me more like scamming of innocent, caring homeowners. Govt ineptitude coupled with industry keeping its mouth shut for fear of killing the approaching golden goose.

From where I sit, I see that we DO NOT NEED to change what’s already installed in homes to meet the immediate climate change targets. Households can both save money and meet said emissions targets almost overnight. How? By the controls industry FINALLY pulling their collective digits out & delivering homeowner-friendly controls. This dearth of truly homeowner-friendly controls has been a major root cause of our over consumption & hastened our pending disaster.

The bimetallic strip thermostat was invented in the 1800s. It transitioned into homes in the 1960s with central heating. The 70s saw the awakening of environmentalism, as energy scarcity reared its head and costs rose, and that drove the market for electronic Building Management Systems for commerce. Manufacturers refused to consider the needs of homeowners. So-called Smart controls, which appeared around 2010, are really an adjunct to the late 70s home automation trend. Has their emergence into the mainstream meant a massive reduction in consumption? Heartbreakingly NO! Despite being so potentially capable, today’s controls remain, to the vast majority of homeowners, like the impenetrable forest in Sleeping Beauty.

Konrad Adenauer, founding father of modern Germany, said, “One needs to look at things so deeply they become simple.” So, no matter what type of heating system homeowners install, it can only EVER be as good as a homeowners ability to use it – its controls.

I recently bought controls from global manufacturers. Disturbingly I found them the antithesis of usable. My estimation is that poorly set up or in correctly used controls are responsible for approx. 1/3 of our excess energy consumption. Frankly, in usability terms, they are appalling. Instructions seem to have barely changed since the 80s. Manufacturers still DEMAND that users are fluent in ‘controls’ and see any failure to understand by users as ''user error'. How very disturbing. Without doubt, manufacturers try hard. They work hard to engage & they always explain / document every nuance. However, this is like shouting louder and louder to someone who's deaf!

During my research, when homeowners were asked why they don’t consider ‘Smart controls’, many said their home, "...doesn't matter in the grand scheme of things.” Truth is, that's a sop, an easy, barely, socially acceptable answer. Further examination uncovered unexpressed fear of change, fear of increased costs, fear of failure (various including inability to master) as well as fear of ‘losing control’ of their home.

It would be yet another environmental disaster to replace systems not currently being controlled properly with different systems not being controlled properly. Replacing existing controls with appropriately user-friendly controls so existing system efficiencies can be maximised would positively impact emissions almost overnight and vitally buy valuable time to not only properly assess alternative energy sources, but to get people properly trained and to configure housing stock so it become truly fir for lower energy sources.

I have tried but I can find no case to be made for replacement without appropriate controls. We need to harness controls technology to support us fallible human beings. We need it TODAY to support and guide us through the impenetrable forest to deliver that all important kiss to awaken the Sleeping Beauty that is planet Earth.

What do you think?

David

Our boiler controls are pretty basic; time and bimetallic strip temperature setting. I'm to be convinced you could beat it though given our current boiler's a bit dumb and only has manual control of its o/p water temperature.

I accept that a more sophisticated boiler/heatpump could have weather compensation, either could show improved efficiency by running at a low power and low flow temperature. I worry though that weather compensation is something that only nerds are allowed to use.

Air temperature isn't the whole story either - radiant imbalance has about as much impact as air temp on how warm people feel, so the thermostat should really try to measure that as well. It accounts for why people in c**p houses turn the heating up when it's cold outside and their walls are colder.

<blockquote><cite>Posted By: HollyBush</cite>In summary you want better controls?

Sounds like you think they are OK when set up and used properly, but most people are unwilling or unable to do so?

I am reminded of a friend that was a building surveyor that authorised humidity detector fans be put in tenants bathrooms and kitchens, possibly other rooms where damp was a problem. This was because tenants were not opening windows and/or switching on the fans if manual. Obvious answer to take out the manual / user error and put automatic ones in.
The problem was 90% of the fans got ripped out and sold, leaving a hole in the window or wall...</blockquote>

In summary, it's not really about what I want but more what the world NEEDS. Controls where they do the very best job that can be done with what you have installed. Controls where they use weather data, where they alter flow temp to minimise fuel used but hit the your comfort needs. Controls that work seamlessly, invisibly effectively.

Think about cars. Before electronics in cars we had a manual choke. Through trial and error (waste in other words) we all eventually learned how far to open it dependant upon temperature etc. Today we have no idea what a choke is! We get in turn the key or push a button and it starts first time every time always. Considering the environmental controls cars also minimise fuel use but this is ALL invisible. No one, but no one gives anything a second thought. If the controls industry designed cars we'd all have to learn about pressurised systems to then set the fuel injection system each time we got in. We'd also have to understand turbo boost and how much is applicable in what circumstance. Truth is if we had to do that cars would now be doing 10mpg on a good day...

Fact is, manufacturers understand it all. We COULD be soooo much more efficient but we are not simply because manufacturers cannot join up the dots and apply some customer empathy. Customers do not give a flying fig about HOW things do what they do so long as it works & works reliably.

I am ashamed of the industry I once contributed to.

When I first read this I thought it was a bit of a rant, which I guess it is, but it is certainly not just a rant - looking at a few recent threads, in particular:

http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17046&page=1#Item_6

and the link

https://www.theheatinghub.co.uk/why-our-condensing-boilers-do-not-condense


I understand better - partly it's about configuration of the system, that initial setup and then partly appropriate control, which can be complex, but it appears rare that both are done well. I am sure there are other issues too, but it is difficult for normal people to get their heads around all the concepts and issues, especially when many manufacturers and installers don't join the dots too.

I hope thread gets more attention.

Posted By: Peter_in_HungaryAll the smart controls in the world won't help with attitudes as above.

Indeed.

And it's probably worth pointing out that a lot of the reason that cars are simpler to use and more fuel efficient than they were is thanks to legislation requiring car manufacturers to do that, not due to them somehow being better than heating manufacturers. It doesn't do anything for ease of repair or cost of servicing either.

But domestic heating equipment is part of the same broken legislative environment as building control et al. Fire safety results kept secret because they are 'commercial'????

Posted By: owlmanIt all reminds me of my "F" gas aircon engineer friend. He gets exasperated after call-outs to heat pump systems where the client keeps switching the whole thing off and on, buggering up the programme, which they then can't re-set, despite him originally setting it on auto, with temp and time of day set backs etc. All the clowns need to do is use the remote control to make minor temporary adjustments but leaving the main programme on auto.

This unwillingness to use simple controls if fairly endemic

One could argue that the fault is with the designers who apparently made the main on/off switch very accessible and either didn't provide or didn't make accessible an adjacent equivalent of the controls on the remote.

I shared a house with an electronics student, who was the only one out of us who could program the VCR (remember them?)

Another of our housemates was a psychology student who couldn't understand how anyone could design VCRs to be so difficult for most humans to interact with.

20 years later, they are now married, with kids who have no idea what VCRs were or how difficult they were to use, they all watch TikTok which 'just works' intuitively.

Most time/temperature controllers seem to be based on the VCR generation of programming techniques, and so are inaccessible to most humans. They need to be replaced with TikTok style controllers.

I've done my own “smart” heating control. If anything, my oil use has gone up slightly but there are a lot of confounding factors, not least the probable sludging up of my radiators [¹] but also increased comfort. Still, I suspect that to have got the increased comfort with the simple thermostat would have needed burning even more oil.

Posted By: DavidNDMy estimation is that poorly set up or in correctly used controls are responsible for approx. 1/3 of our excess energy consumption.

What do you mean by “excess” energy consumption? What accounts for the other 2/3rds of it? How did you come to this estimation? (I'd not be surprised if that was a reasonable figure, depending on what you mean by “excess”, but still it'd be nice to understand where it came from.)

[¹] http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17038

The thing that seems to be missing from so many heating control systems is the ability to control different zones/rooms independently.

When I last looked into all this (5-7 years ago?), things like Nest didn't offer this - but has that changed now?

I ended up going for a Honeywell system that has a central controller and then a TRV on each radiator that can communicate by RF with the central controller. It just about works but is a bit of a constant hassle partly because of the controls - they are a bit clunky in general but there are also certain things you have to remember how to do - for example, how to re-pair a radiator controller with the main unit if you replace it or the battery runs out or whatever. The instructions for these things are bad, and the methods not entirely intuitive. There are all sorts of aspects of how it works that are not really clearly explained (things like whether individual radiator controllers over-ride central commands or vice versa) and I have to keep a notes document for myself so that I can remember how to sort stuff out from one winter to the next.

Once it's all set up, it's kind-of usable by anyone (at least the individual radiator controls are) but relies on me keeping an eye on it and doing quite a lot of fiddling around. I think many people would have just given up on it by now.

Maybe the latest versions of 'smart' systems can now do zoned heating with more user-friendly control?

My parents had an air source heat pump system put in last year, and I was a bit surprised that it was just installed with the longstanding conventional control arrangement of a single central thermostat and then TRVs in each room. I don't think we should be installing that kind of control system in 2021. We should have systems that allow you to programme timed sequences for each room/zone independently, and turn off/on individual rooms easily from the central controller, using an intuitive and user friendly interface.

So I agree with quite a lot of the OP.

Posted By: bhommelsMy take on the desire for room-by-room controls is that the insulation is not good enough (yet). Either that or the house is huge.

+1.

Also, my experience of people is that one day they are warm enough at 20C and the next cold at 21C so unless a 'smart' system can actually cope with this it still isn't going to work in the real world. I wonder if we are simply over thinking this one.

Or a woolly jumper.

Posted By: WillInAberdeen*another* jumper.

An internal partition wall or intermediate floor with acoustic wool in it, has a U-value about 0.5, which is well able to maintain a temperature difference of say 3 degrees between say a lounge and a bedroom, given that the external walls can maintain a difference of up to 25deg from inside to outside.

...assuming no heat exchange through air movement and/or thermal bridging, everybody staying where they are and keeping the doors shut....

I like a bedroom to be say 21deg in the evening, maybe 15-17deg overnight, and about 19deg when I wake up. I like a lounge to be unheated overnight and through the day, and perhaps 21deg in the evening. By tweaking the timing of the different zones, I can just about do this, but it needs luck and lots of tweaking. Shouldn't be difficult for controllers to just do this, don't know why they don't. Most cars can organise different temperatures for the driver and passenger.

This is temperature profiling (in time), which as you say is well possible with today's controllers. As you well know it will only work if all time constants in the system are small, and temperature profiling is achievable with a boiler feeding radiators in a lossy house with low solar gain. Not something to aim for (and neither is the car analogy) I would think.

I don't think your picture of the heat flows in a passivhaus is very accurate and is probably misleading.

One major omission is solar gains through the windows which should be quite large in winter. The south side of our house is always a degree or two warmer than the north side.

Another omission is that even with all the doors closed (which is very far from normal in our house, and probably most houses) there will still be airflow under or over the doors between rooms and lobbies etc.

And of course the air flow may carry the main heating input.

The time constant is likely to be measured in days, or at least tens of hours.

I suggest trying one before pooh-poohing the idea.

@WiA: How do you arrive at a time delay of only 3 hours while having U=0.1? Or does the 3hrs apply to the internal walls?

When I put a lightweight lay-up of wood cladding, 300mm mineral wool and plasterboard (U=0.1) into the onilne calculator of ubakus.com, I get a phase shift of almost 9 hours, which is line with what I would expect from my experience with my house (EWI'ed brick: U=0.14 and t=14 hrs).

I don't know where you live but in my neck of the woods the external temperature is rarely constant for 9 hours, nevermind 14. With these time constants it is practically impossible to temperature profile my house, except perhaps when it is really cold outside and there is no solar gain to speak of, and we have not invited a load of warm bodies in.
BTW the 14h delay made the task of tuning the weather compensation heating curve really difficult, especially when considering the in-screed UFH having a reaction time of 3h in addition.

One take home thing from your post is that it would be nice to have MVHR with variable efficiency/bypass function so that it could let in colder air when desired, and possible, instead of leaving it to the occupants to open windows or such like. I could see a system of room-thermostat-controlled-variable-bypass-MVHR work for airtight, well insulated homes. It would be limited in what it can achieve though.

@WiA: Frequentist approach to heating cycles, very clever. I hope that in practice the disturbances (weather, people, solar gain, etc) are small compared to the temperature cycles so it does not get all messed up! I guess you could design it such that you have the periodic cycles as a baseline and then have something more interactive to act on the deviations/disturbances?

What I would like to see is predictive controls where an online weather forecast is used to anticipate what is going to happen and act accordingly. Not so useful perhaps in the middle of winter, it would mostly prevent over- and undershoots in the shoulder months (the more insulation, the more shoulder months). It would require careful tuning to the particular situation, though perhaps a self learning controller could do this for you.