I know it’s a lot less popular in the US, but has anybody figured out TRVs that work in the US on boiler with hot water radiators? I looked into it last year and wasn’t able to find anything.
Why would a trv not work in the US?
I would guess that the pipe thread standards are different.
Well that should be easy to fix!
My view is that Evohome is the best for zone control and was actually the first smart home heating solution, it’s the professionals choice here in the UK. For local control you’ll need ramses_cc
A lot of people close doors of rooms not in use, so the flow between the rooms is minimized. I myself have started monitoring room temperatures with TRV independent sensors and have found that in my home, room temperatures vary by 1-1.5 °C if unregulated (i.e. in summer due to high temperature outside and now in fall due to low temperature outside).
This is simply because one side of the house is being heated more as it is facing east/south-east. It gets the morning and noon sun. The other half of the house only gets the weaker evening sun.
So I see quite a difference in consumption depending on which rooms I heat to which temperature.
I think you are primarily correct if you heat your home constantly (i.e. even when you are at work or out in the town for a few hours). I heat only when home and “full” temperature only in the rooms I am actively using (e.g. 20 °C in living room but 18 °C in office, guest toilet etc.
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If you want to save energy, then surely moving to battery powered is consuming more energy. Batteries always have lower efficiency and especially things like wireless charging have very poor efficiency.
Where do you buy them?
yes, that thought has crossed my mind…
Hard to find useable figures on that though.
in the end we might be talking about saving decimal percentages. 15 min 2100 w from the grid in peak hour, or 15 min on a battery vacuum, charged during sun hours. Daily.
You tell me…
If anything,. there is no transportation cost Nor taxes on that ( In NL where I live, the energy costs are more than 50% taxes of various sorts… even though the government reduced some of those currently, they wont be doing so forever.)
For wireless charging I recall reading that efficiency is below 70%. That is also why they are so reluctant to offer wireless charging for cars (even though possible).
For everything else I do not have reliable numbers.
But you need to take into account:
- voltage conversion losses (also why 5V with 3.6 V native voltage is always lossy e.g. in powerbanks). These also include all the electronics needed to convert, which is usually also seen by how warm the chargers get.
- loss from self-discharge. Even though low, self-discharge probably becomes relevant when we are taking high powered devices.
Not sure if aging/capacity loss over time has an impact on power consumption but it definitely impacts the costs of the device.
Very personal, but I try to use e.g. as little battery powered power tools, vacuums etc. as possible because the batteries are expensive and the overall additional cost (battery replacement, usually higher retail price and above mentioned losses) simply make them unappealing to me (with very few exceptions).
If I could, I would even power my TRVs and sensors with grid power rather than batteries (also more environmentally friendly).
thats all very interesting stuff indeed, thanks for the perspective!
my gripe from before with battery powered stuff mainly was their lack of power… Had a huge lawnmower that just couldn’t do what it was supposed to. neither did the grid powered btw, so I had to move to a petrol device…
other than that, I am mostly worried bout the true environmental consequences: where is all the Lithium mined, and under what circumstances. Seems hardly a future proof proposition either.
Ill check the charging for a few days on the vacuums (have a few here in comparison) and might be able to tell how that compares to regular Grid suction 
It sounds like we actually have a very similar experience. I have temperature sensors in every room and see the same thing, i.e., a 1-2°C variance when the heating is off. Likewise, I attribute that to the Sun. Like you, we keep doors closed where possible, don’t heat occasionally-used rooms (toilet, utility room etc) to full temperature, and have automatons to allow the house to drop to 14°C if everyone is out (plus to turn off heating if an external door is left open for some reason).
Despite all this, I believe the benefit of investing in Smart TRVs vs normal “dumb” TRVs is a bit marginal, at least in my case. (My case == balanced radiators, carefully adjusted dumb TRVs, temperature sensors in every room, and boiler automatically controlled to minimize its use)
The additional benefit of Smart TRVs would be that I could automatically turn off radiators if I know a room is unoccupied. However, those rooms will still be heated indirectly by adjacent rooms, through the uninsulated internal walls and floor (even with the door shut). The external walls and loft/attic are pretty well insulated, so it is inevitable that a lot of the heat trapped inside the house will equalize with the unoccupied unheated room. Even on a cold day, my unused guest bedroom will end up at about 17°C, perhaps 2°C cooler than adjacent rooms. So, in the extreme case, the difference between leaving the radiator on 24/7 in the unoccupied room versus diligently (or automatically) turning it off is the energy required to raise the temperature in that room by about 2°C. That’s a saving, but I think it’s a much smaller saving than many people would hope for.
In more practical terms, it is not a chore to manually turn off (or turn down) radiators in unoccupied rooms (e.g., if my guest room is going to be unoccupied for a while). Compared to this situation, Smart TRVs might be useful for turning off radiators in occupied rooms during different parts of the day (e.g., turn off bedrooms radiators if everyone has gotten out of bed). This would definitely be optimal, but I think the energy saving would be a fraction of the extreme case above. That leaves me thinking the few hundred Euro I could spend on smart TRVs might be better spent on more rockwool for the attic, or even on thicker blankets for the beds 
I completely knowledge that my experience won’t translate for everyone. So much depends on the design of your house and how you use it. In my case, its a ~100 sqm recently refurbished and insulated semi-detached two story house, typical of Irish/UK housing stock, which is at least partially occupied during most of the day. However, I hope my experience will help some people assess whether a Smart TRV project is the most effective way to optimise energy this winter.
I agree with you, which is why I decided not to go the expensive wifi/zigbee etc. TRVs that cost 40+€ each.
I decided to go with BLE TRVs that cost ~15€ each new (and I bought some second hand, so all 8 cost me ~80€).
I do not know if I can save thise 80€ or how long it would take (because we have “district heating” and the sensors cannot be read by me).
But I have my automations and scripts set up in a way that each TRV is adjusted based on a scenario. So like you, each room has a certain setting for us doing home office, after work relaxing, sleeping, being out briefly or out for a longer time.
So depending on the scenario we activate a script via the companion app (i.e. Android tiles) and all TRVs are adjusted.
Whilst manual adjustment is not a chore, the 80 € I feel are acceptable for this additonal comfort.
Added benefit is that I can track the setting of each TRV and plot it against the in-room sensors.
So I can see how quickly which room heats up or loses heat. So when do I need to turn on and when off.
But for sure I would not do this with the expensive TRVs. I doubt they will refinance themselves except through the “comfort”.
P.S.: Plus, if I forget before leaving the house or when a day trip turns into a long weekend, I can remote adjust the TRVs 
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The Plugwise system mentioned above has valves for floor heating.
Correct, the pipe threads are different and also the style of radiators is different. Europe uses a lot of wall panel style where the US uses a lot of floor radiators.
In theory yes, but I haven’t found any. Hence the question.
C.P.Snow
Thermodynamics
First Law - You can’t win.
Second Law - You can’t even break even.
Third Law - You can’t get out of the game.
My experience of TRVs and thermostats over last 2 years is that it didn’t seem to make much difference to how often I had to get a home heating oil delivery.
I set it up to mainly to warm the house when I came home from work/get up in morning or come home from a holiday. Thought a week with minimal heating must save alot while away(Covid put an end to that). Hated adjusting the little white box that controlled the heating in the utility room.
Found home assistant much easier to work from my phone. Fitted Bluetooth TRVs on several rooms. Other less used rooms have manual TRVs set to minimal. Does get rooms warm when needed but have never felt it made any money savings.
I think it just allowed me to heat more when I was there to enjoy it. Enjoyed the learning all about this and internal heating from the smugness of getting it to work.
I suspect I would have spent my money better if I had invested in better insulation but I think the insulation forums are not as interesting as the home assistant community.
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Hey,
Quick question.
I have a RPi4 running Hass OS. A external powered USB 3 hub is connected to the USB3 port on my pi. Should I connect an extension lead and coordinator(not blue ports therefore USB2? Does this matter?)) to the USB2 port of the pi or to the powered USB3 port of the hub.
There are any number of places to get plumbing adapters from. I usually start at the garden centre.