(I was debating whether this question was more appropriate for GQ or IMHO, but since this question hopefully has a factual answer, I’m putting it here)
I live in a NYC high rise co-op with hot water radiators behind sheet metal covers. With the latest weather, it’s become nigh on impossible to keep the heat consistently at a comfortable level without having to daily change the settings on the radiators.
I do see that there are thermostatically controlled valves, however, since the system is shared by the entire building, I can’t open it up to replace the valves (although I can remove the knob). I need something that will attach to the existing valve stems to control them. From my work with in-ground swimming pool filter systems, I know such a device is called an actuator, but I haven’t been able to find one that will work in this situation (especially since they don’t all have the same control - one valve is about 7/8 of a turn from all off to all on, while the other two are probably two full turns for the same cycle).
Well, it’s unlikely that my radiators (installed in the 1950s) would have a metric screw fitting as these require, but it’s a step in the right direction (maybe there’s a US version?). it’s also unclear how much rotation they can provide.
You may not need something that turns so much. I’ve found with my various radiator valves that you can turn them from closed about one quarter of the way before anything happens at all, then you have about 10 degrees of turn before you effectively have full flow. Cranking the valve the rest of the way open has little effect. So you might be able to get away with an actuator that only turns a quarter or half circle, you just need to get the valve at the right position first. Of course your system could be different, so it’s worth doing some testing.
Running with Scissors:
The difficulty you are encountering with the weather aside: Under normal circumstances, how is your heat controlled?
Is there a thermostatic controller, or do you manually adjust your temperature by simply opening/closing a valve? If the former, a HVAC control tech should be able to help. If the latter, your system would be a literal nightmare to automate, especially on the fly… Forget that notion and put up with the inconvenience till the weather changes. Then be prepared for a major $$ investment in automation.
Because you cant necessarily automate old, crusty, valves designed for manual operation. Replacing valves for such would require an entire system shutdown (as you seem to be aware), and in this kind of weather your neighbors may become cranky.
As an afterthought:
If you insist on pursuing this, you could use the existing valves as stop valves, thereby allowing the installation of a new actuated control valve system that is driven by a thermostat, but please give up on the idea of automating what you have now. Good luck.
Well, yeah, that’s why I posted this question in the first place. bob++ posted a potential solution, and since there have to be plenty of people in this same situation, I’m assuming there must be something out there.
And while your idea of installing an additional activated valve has merit, that would involve (at the least) cutting a pipe, and I’m pretty sure the entire heating system (including the radiators) belongs to the co-op, not us, so that wouldn’t be allowed.
I’m going to consult with our maintenance dept and see if they have any “official” solutions. In the meantime, any additional suggestions are appreciated.
I don’t see why you need to be so dismissive gogogophers. If the existing valves are functional, it doesn’t seem out of the ordinary to wonder if there’s some sort of clamp-on actuator that could turn them. In most cases the valve handle/knob is easy to remove with just a single screw, then you have access to the smaller valve stem which could be easier to fit something to. I suspect such a device would require plugging in to an electric outlet, since anything with batteries or fluid expansion or whatever wouldn’t provide enough torque or throw to turn one of those valves. All that said, the only way any actuator that fits on such a valve (or any valve) would work is if the OP’s unit is normally over-heated. You can only turn the heat down at the radiator, not up.
There’s a surprisingly large number of systems out there that rely on nothing more than outdoor reset (tying the supply water temperature to the outdoor temperature). There’s likely no automation beyond that, such as sun or wind sensors, remote monitors, flow controls, remote monitoring, etc. This is especially true for steam systems converted to hot water. For a lot of buildings and landlords that’s considered good enough, but it usually leads to the building being somewhat overheated. The tenant with the coldest apartment is the one that complains the most, so the boiler temp is dialed up until they’re satisfied. Everyone else either opens windows or futzes with their radiator valves to compensate. I’d love to have something like this that I could install myself without having to dismantle anything.
What may seem easily do-able to you raises all kinds of red flags for me. I’ve had 25 years of industrial process control (temp., flow, pressure, etc.) experience dealing with such. So yes, it is “out of the ordinary to wonder if there’s some sort of clamp-on actuator that could turn them.”
Mind you, not impossible, but unrealistic… There is nothing that money and time can not cure, so pick your poison.