Hi all,
I live in NYC and have the ubiquitous single pipe steam radiator with a large valve for controlling heat. I see lots of European z wave devices for thermostatic valves, but not seeing much USA wise. Has anyone come across anything I could use to control my heat?
Thanks in advance.
I’m not aware of any smart valve controllers made for the US For residential systems. And particularly not for steam systems. Typically they are not to code as they can unbalance the system pretty easily. And a single pipe system almost always means a vent, not a valve.
In Europe, most of the residential systems are two pipe water systems (not steam) and already connected to a thermostat. So the very many smart valves on the market there are just dealing with an entirely different kind of design.
Are you in an apartment? If so, there’s probably not much you can do unless the landlord decides to upgrade the whole building system.
If you are in a single-family home, you may have more options, but they won’t be inexpensive single room choices like the European designs.
Hi JDR, Happy to see you’re still around helping people out! Apologies for long post.
So, I’m going to end up DIYing it. I am indeed in an apartment and understand the situation with unbalancing the system as well as control usually being done on the vent side, not the intake side. In our case, we have a big open/close valve on the steam intake, and a default/not thermostatic vent. The big knob obviously turns the heat/steam off and on, and I know factually that people regularly use it in my building to try to cool it down, as our radiators are way overpowered and we’re all sweating to death with the windows wide open in the dead of NYC winter and neighbors have discussed using the knob to cool off. I have little faith in the system being balanced in the first place, and we’re closer to the basement boiler than most apartments! So it comes down to, I’m gonna control that steam intake with a manual knob, in which case I get a binary and laborious situation, or I’m gonna automate it and use smartthings to respond dynamically to temp. This is obviously flawed in at least one way – all I can actively do is disable the steam entering, but I can not force steam to enter. If it get’s cold and my knob is off, turning it on doesn’t necessarily mean I’ll get heat anytime soon, but in the winter, the steam is flowing pretty regularly, and I’m OK with a slight delay in heat kicking in if it means I’m not drenched in sweat every morning. I literally run our window air conditioner at night sometimes because even with all windows open and 20 degree weather, it’s still far too hot to sleep!
Anyway, rather than replace the valve with a smart valve or anything involving any real modification to the boiler (that I’m renting), I’m going to use a nodemcu, ST anything, a servo or stepper motor, assorted arduino goodies, and a not-yet-designed 3d printer mechanism of some sort to just spin the knob open and closed in response to temperature!
Wish me luck.
Can’t wish you luck on anything that violates local safety codes, but I will wish you luck in finding a future solution that does meet code. 
There are radiator covers that you can look at that don’t involve changing anything about the radiator flow, and I know they are popular in New York City apartments, but I honestly don’t know how well they work except for a highly engineered one (The Cozy) which has to have controls installed at the boiler as well. Like you say, they won’t let you make the room warmer, but they can disburse some of the excess heat when you want it cooler.
All of this is a big issue in New York City because of the wasted energy use, so the city is looking into several initiatives to try to get the landlord to provide more individual control for steam heated buildings. But I wouldn’t expect many results from those initiatives until at least 2025.
Its your position that turning the big, easily accessible knob with “<–Open Close–>” on it, on the floor of my bedroom, would be a code violation?
I don’t know, you’d have to check your local jurisdiction, but my understanding is that automating that knob is a code violation in single pipe steam multi family units in a number of US jurisdictions. Which is why you can’t easily find a readybuilt smart device to do it.
I myself am a quad in a wheelchair, and this is a big issue for people in a similar situation. I did check some of my wheelchair technology sources and everybody says the same thing about New York City apartments: they won’t let you automate that knob even with an accessibility exemption. The landlords want to be certain that there is someone actually in the apartment at the time the setting is changed.
But let us know if you find out anything different. 
Hello, late into this thread but intrigued by the conversation.
I also live in NYC and have two steam radiators that requires constant attention to regulate the temperature. In cold weather (below 40 degrees) the steam is on constantly (supplied by the building). I can open and close the valve manually (fully open, partially open, closed) and nuance the temperature.
Like Stefan mentioned, I know there are systems that can control the use of this knob with a thermostat connected to a smart system (some kind of network-connected servo), but I’m not finding many commercially-available products, only well-intentioned hacks that do the job, but who knows if compliant.
I own this apartment, and recently renovated with two new steam radiators. They work well, with effort. Seeking to automate this process. I’m using a Nest thermostat on Apple HomeKit (connected via Homebridge). I’m willing to build this myself and not worried about a pesky landlord, building codes and HOA rules be damned.
I’m curious if Stefan or others have found a solution. thanks!